feat(overlay): add optional subtitle selection modal

- Add primary and secondary mpv track selection from the overlay
- Support configurable sequence shortcuts with conflict detection and hot reload
- Document settings, shortcuts, and generated config defaults

changes/subtitle-selection-docs.md

@@ -0,0 +1,4 @@
+type: docs
+area: config
+
+- Documented the subtitle selector setting, shortcut override, and primary/secondary track controls.

changes/subtitle-selection.md

@@ -0,0 +1,5 @@
+type: added
+area: overlay
+
+- Added an optional Catppuccin subtitle selection modal for primary and secondary mpv tracks. Enable it in Settings under Behavior, then press g followed by s. Disabling it restores mpv's subtitle selection binding.
+- Single-key actions take priority over configured sequence prefixes. Conflicting sequences are disabled with a warning, and the existing y commands stay reserved.

config.example.jsonc

@@ -6,6 +6,15 @@
  */
 {
 
+  // ==========================================
+  // Subtitle Selection
+  // Select primary and secondary mpv subtitle tracks from the overlay.
+  // Hot-reload: enabling or disabling updates the session shortcut immediately.
+  // ==========================================
+  "subtitleSelection": {
+    "enabled": false // Use the SubMiner modal to select primary and secondary subtitle tracks. When enabled, its shortcut overrides mpv subtitle selection. Values: true | false
+  }, // Select primary and secondary mpv subtitle tracks from the overlay.
+
   // ==========================================
   // Japanese Subtitle Generation
   // Generate timed Japanese subtitles from local audio using whisper.cpp.
@@ -223,6 +232,7 @@
     "openRuntimeOptions": "CommandOrControl+Shift+O", // Accelerator that opens the runtime options modal.
     "openJimaku": "Ctrl+Shift+J", // Accelerator that opens the Jimaku subtitle search modal.
     "openTsukihime": "Ctrl+Shift+T", // Accelerator that opens the TsukiHime subtitle search modal (configured secondary/Japanese primary tabs).
+    "openSubtitleSelection": "g-s", // Open subtitle selection when enabled. Use g-s to press g then s. Set null to unbind.
     "openSubtitleGeneration": "Ctrl+Shift+G", // Accelerator that opens the standalone Japanese subtitle generation modal.
     "openSessionHelp": "CommandOrControl+Slash", // Accelerator that opens the session help / keybinding cheatsheet.
     "openControllerSelect": "Alt+C", // Accelerator that opens the controller selection and learn-mode modal.

docs-site/configuration.md

@@ -1117,6 +1117,14 @@ When the manual merge popup opens, SubMiner pauses playback and closes any open
 
 <a :href="withBase('/assets/kiku-integration.webm')" target="_blank" rel="noreferrer">Open demo in a new tab</a>
 
+## Subtitle Selection
+
+Enable **Settings → Behavior → Subtitle Selection → Enabled** to choose mpv's primary and secondary subtitle tracks from a SubMiner modal. The feature is disabled by default. The dialog uses the same overlay focus and subtitle suppression behavior as the other modals.
+
+Press `g` then `s` to open it. Both selectors include **None**. Choose different tracks and click **Apply** to load them into mpv, or close the dialog to keep the current selection. Embedded and already-loaded external subtitle tracks are listed with their title, language, and codec when available.
+
+`subtitleSelection.enabled` controls the feature. `shortcuts.openSubtitleSelection` changes its shortcut, or accepts `null` to unbind it. Enabling the feature overrides mpv's binding for that shortcut when its first key is free; disabling it restores mpv's binding. Existing single-key actions take priority over sequences; see [shortcut conflicts](/shortcuts). Both settings apply immediately. See the [generated configuration example](/config.example.jsonc) for defaults.
+
 ## External integrations
 
 ### Jimaku

docs-site/public/config.example.jsonc

@@ -6,6 +6,15 @@
  */
 {
 
+  // ==========================================
+  // Subtitle Selection
+  // Select primary and secondary mpv subtitle tracks from the overlay.
+  // Hot-reload: enabling or disabling updates the session shortcut immediately.
+  // ==========================================
+  "subtitleSelection": {
+    "enabled": false // Use the SubMiner modal to select primary and secondary subtitle tracks. When enabled, its shortcut overrides mpv subtitle selection. Values: true | false
+  }, // Select primary and secondary mpv subtitle tracks from the overlay.
+
   // ==========================================
   // Japanese Subtitle Generation
   // Generate timed Japanese subtitles from local audio using whisper.cpp.
@@ -223,6 +232,7 @@
     "openRuntimeOptions": "CommandOrControl+Shift+O", // Accelerator that opens the runtime options modal.
     "openJimaku": "Ctrl+Shift+J", // Accelerator that opens the Jimaku subtitle search modal.
     "openTsukihime": "Ctrl+Shift+T", // Accelerator that opens the TsukiHime subtitle search modal (configured secondary/Japanese primary tabs).
+    "openSubtitleSelection": "g-s", // Open subtitle selection when enabled. Use g-s to press g then s. Set null to unbind.
     "openSubtitleGeneration": "Ctrl+Shift+G", // Accelerator that opens the standalone Japanese subtitle generation modal.
     "openSessionHelp": "CommandOrControl+Slash", // Accelerator that opens the session help / keybinding cheatsheet.
     "openControllerSelect": "Alt+C", // Accelerator that opens the controller selection and learn-mode modal.

docs-site/shortcuts.md

@@ -88,6 +88,7 @@ Mouse-hover playback behavior is configured separately from shortcuts: `subtitle
 | `Ctrl+Shift+T`     | Open TsukiHime subtitle search modal (EN/JA tabs)       | `shortcuts.openTsukihime`                 |
 | `Ctrl/Cmd+N`       | Toggle overlay notification history panel                | `shortcuts.toggleNotificationHistory`      |
 | `Ctrl+Alt+C`       | Open the manual YouTube subtitle picker                  | `keybindings`                              |
+| `g` then `s`       | Select primary and secondary subtitles, when enabled     | `shortcuts.openSubtitleSelection`                                                               |
 | `Ctrl+Alt+S`       | Open subtitle sync (subsync) modal                       | `shortcuts.triggerSubsync`                 |
 | `Ctrl/Cmd+A`       | Append clipboard video path to mpv playlist              | `shortcuts.appendClipboardVideoToQueue`    |
 | `\`                | Toggle subtitle sidebar                                  | `subtitleSidebar.toggleKey` (overlay) / `shortcuts.toggleSubtitleSidebar` (mpv session binding) |
@@ -98,6 +99,8 @@ Mouse-hover playback behavior is configured separately from shortcuts: `subtitle
 
 The stats toggle is handled inside the focused visible overlay window. It is configurable through the top-level `stats.toggleKey` setting and defaults to `Backquote`.
 
+Enable the subtitle selector in **Settings → Behavior → Subtitle Selection**. Its shortcut overrides mpv subtitle selection only while enabled. In the focused overlay, press the second key within one second. Single-key bindings take priority: if `g` already has an action in SubMiner or mpv, `g-s` is disabled with a conflict warning, and `g` still runs immediately. Remap the sequence or remove the conflicting single-key binding. The existing `y` prefix is reserved for its built-in commands. mpv bindings are checked on connection, configuration changes, and overlay focus; refresh the overlay after changing another script's bindings. See [subtitle selection](/configuration#subtitle-selection).
+
 The subtitle sidebar toggle is overlay-local and only opens when SubMiner has a parsed cue list for the active subtitle source.
 
 In the sidebar, `Enter` seeks the keyboard-focused cue. `Space` keeps its configured playback action, normally pause/resume, even when a cue has focus.

docs/architecture/README.md

@@ -35,6 +35,8 @@ Update checks and startup launcher migration share a serialized update-state sto
 - `src/core/services/subtitle-generation*.ts` shares local whisper.cpp transcription, safe model downloads, and progress between the launcher and Electron. Optional dialogue mode retains both Silero-detected speech and other audible sections, omits confidently silent gaps, decodes passages independently, and restores original media timing. `src/main/runtime/subtitle-generation-runtime.ts` owns the overlay job lifecycle and only loads completed subtitles into the same local media; `src/shared/subtitle-generation*.ts` owns configuration, the multilingual model catalog, and IPC contracts. The overlay runtime retains a session model selection, validates picker requests through IPC, and keeps external model paths authoritative.
 - Subtitle model recommendations use bounded `nvidia-smi` and Whisper CUDA discovery probes in `subtitle-generation-acceleration.ts`. The overlay runtime caches results by executable path for 30 seconds and exposes acceleration status through the existing status IPC. Recommendations do not alter model selection or transcription arguments.
 - `subtitle-generation-reference.ts` ranks mpv's loaded text subtitle tracks, excludes signs/songs and forced references, and extracts timing hints with FFmpeg. The overlay and launcher snapshot references only for matching media, including active subtitle delays. Hints guide long-passage cuts with or without VAD; they never limit audio coverage or replace Whisper timestamps.
+- `src/main/runtime/subtitle-selection.ts` reads and validates mpv subtitle tracks and applies primary/secondary selections. Its opt-in session shortcut opens the shared overlay modal window, with renderer focus and subtitle suppression handled by the modal registry.
+- `src/shared/session-key-sequences.ts` rejects sequence prefixes reserved by single-key actions. The session-binding compiler reserves configured and built-in overlay keys; `src/main/runtime/session-bindings-runtime.ts` adds active mpv bindings and publishes the effective list to both the plugin artifact and the renderer through `session-bindings:changed`. mpv no-op `ignore` bindings do not reserve prefixes.
 - `src/renderer/` owns overlay rendering and input behavior.
 - `src/config/` owns config definitions, defaults, loading, and resolution.
 - `src/types/` owns shared cross-runtime contracts via domain entrypoints; `src/types.ts` stays a compatibility barrel.

plugin/subminer/session_bindings.lua

@@ -91,6 +91,10 @@ function M.create(ctx)
 	end
 
 	local function key_code_to_mpv_name(code)
+		local first, second = code:match("^Key([A-Z])%-Key([A-Z])$")
+		if first and second then
+			return string.lower(first) .. "-" .. string.lower(second)
+		end
 		if KEY_NAME_MAP[code] then
 			return KEY_NAME_MAP[code]
 		end
@@ -187,6 +191,110 @@ function M.create(ctx)
 		return bindings
 	end
 
+	-- Match letter strokes, including mpv's uppercase spelling for Shift.
+	local function letter_key_signature(value)
+		if type(value) ~= "string" then
+			return nil
+		end
+		local modifiers = {}
+		while true do
+			local modifier, rest = value:match("^([%a]+)%+(.+)$")
+			if not modifier then
+				break
+			end
+			modifier = string.lower(modifier)
+			if not MODIFIER_MAP[modifier] then
+				return nil
+			end
+			modifiers[modifier] = true
+			value = rest
+		end
+		if not value:match("^[a-zA-Z]$") then
+			return nil
+		end
+		if value:match("^[A-Z]$") then
+			modifiers.shift = true
+		end
+		local parts = {}
+		for _, modifier in ipairs({ "ctrl", "alt", "shift", "meta" }) do
+			if modifiers[modifier] then
+				parts[#parts + 1] = modifier
+			end
+		end
+		parts[#parts + 1] = string.lower(value)
+		return table.concat(parts, "+")
+	end
+
+	local function external_single_keys()
+		local keys = {}
+		local native = mp.get_property_native and mp.get_property_native("input-bindings") or {}
+		for _, entry in ipairs(native or {}) do
+			local signature = letter_key_signature(entry.key)
+			if
+				signature
+				and type(entry.cmd) == "string"
+				and type(entry.priority) == "number"
+				and entry.priority >= 0
+			then
+				local owned = entry.owner == "subminer"
+					or (
+						entry.owner == nil
+						and (
+							entry.cmd:match("script%-binding%s+['\"]?subminer/")
+							or entry.cmd:match("script%-message%s+['\"]?subminer%-")
+						)
+					)
+				local previous = keys[signature]
+				if
+					not previous
+					or entry.priority > previous.priority
+					or (entry.priority == previous.priority and owned)
+				then
+					local command = entry.cmd:match("^%s*(.-)%s*$")
+					local flags = {
+						["no-osd"] = true,
+						["osd-bar"] = true,
+						["osd-msg"] = true,
+						["osd-msg-bar"] = true,
+						["osd-auto"] = true,
+						["expand-properties"] = true,
+						["raw"] = true,
+						["repeatable"] = true,
+						["nonrepeatable"] = true,
+						["nonscalable"] = true,
+						["async"] = true,
+						["sync"] = true,
+					}
+					while true do
+						local flag, rest = command:match("^(%S+)%s+(.+)$")
+						if not flags[flag] then
+							break
+						end
+						command = rest
+					end
+					keys[signature] = { priority = entry.priority, owned = owned, ignored = command == "ignore" }
+				end
+			end
+		end
+		return keys
+	end
+
+	local function sequence_conflict(binding, singles)
+		local code = binding.key and binding.key.code
+		local prefix = type(code) == "string" and code:match("^(Key[A-Z])%-Key[A-Z]$")
+		if not prefix then
+			return nil
+		end
+		local names = key_spec_to_mpv_bindings({ code = prefix, modifiers = binding.key.modifiers }) or {}
+		for _, name in ipairs(names) do
+			local existing = singles[letter_key_signature(name)]
+			if existing and not existing.owned and not existing.ignored then
+				return name
+			end
+		end
+		return nil
+	end
+
 	local function normalize_cli_args(cli_args)
 		if type(cli_args) ~= "table" then
 			return nil
@@ -391,17 +499,23 @@ function M.create(ctx)
 		local next_binding_names = {}
 		state.session_binding_generation = (state.session_binding_generation or 0) + 1
 		local generation = state.session_binding_generation
+		local singles = external_single_keys()
 
 		for index, binding in ipairs(artifact.bindings) do
 			if not is_supported_binding(binding) then
-				subminer_log(
-					"warn",
-					"session-bindings",
-					"Skipped unsupported session binding from artifact"
-				)
+				subminer_log("warn", "session-bindings", "Skipped unsupported session binding from artifact")
 			else
 				local key_names = key_spec_to_mpv_bindings(binding.key)
-				if key_names then
+				local conflict = sequence_conflict(binding, singles)
+				if conflict then
+					local message = "Disabled sequence "
+						.. tostring(binding.originalKey or binding.key.code)
+						.. ": mpv already uses "
+						.. conflict
+						.. ". Single-key bindings take priority."
+					subminer_log("warn", "session-bindings", message)
+					show_osd(message)
+				elseif key_names then
 					for key_index, key_name in ipairs(key_names) do
 						local name = "subminer-session-binding-"
 							.. tostring(generation)
@@ -418,7 +532,8 @@ function M.create(ctx)
 					subminer_log(
 						"warn",
 						"session-bindings",
-						"Skipped unsupported key code from artifact: " .. tostring(binding.key and binding.key.code or "unknown")
+						"Skipped unsupported key code from artifact: "
+							.. tostring(binding.key and binding.key.code or "unknown")
 					)
 				end
 			end

scripts/test-plugin-session-bindings.lua

@@ -69,6 +69,12 @@ local ctx = {
 			return {
 				numericSelectionTimeoutMs = 3000,
 				bindings = {
+					{
+						key = { code = "KeyG-KeyS", modifiers = {} },
+						actionType = "session-action",
+						actionId = "openSubtitleSelection",
+						cliArgs = { "--session-action", '{"actionId":"openSubtitleSelection"}' },
+					},
 					{
 						key = {
 							code = "KeyO",
@@ -312,7 +318,8 @@ local ctx = {
 						cliArgs = { "--session-action", '{"actionId":"openFuturePanel"}' },
 					},
 				},
-			}, nil
+			},
+				nil
 		end,
 	},
 	state = {
@@ -430,17 +437,11 @@ assert_true(play_next_call ~= nil, "play-next binding should invoke CLI action")
 assert_true(play_next_call[2] == "--play-next-subtitle", "play-next binding should pass CLI flag")
 
 local character_dictionary_manager = find_binding("Ctrl+d")
-assert_true(
-	character_dictionary_manager ~= nil,
-	"character dictionary manager binding should be registered"
-)
+assert_true(character_dictionary_manager ~= nil, "character dictionary manager binding should be registered")
 
 character_dictionary_manager.fn()
 local character_dictionary_manager_call = recorded.async_calls[#recorded.async_calls]
-assert_true(
-	character_dictionary_manager_call ~= nil,
-	"character dictionary manager binding should invoke CLI action"
-)
+assert_true(character_dictionary_manager_call ~= nil, "character dictionary manager binding should invoke CLI action")
 assert_true(
 	character_dictionary_manager_call[2] == "--session-action",
 	"character dictionary manager binding should use generic session action CLI flag"
@@ -474,3 +475,35 @@ assert_true(call[2] == "--mine-sentence-multiple", "CLI action should enter mine
 assert_true(call[3] == nil, "CLI action should not bind a plugin-side digit count")
 
 print("plugin session binding regression tests: OK")
+
+local selector = find_binding("g-s")
+assert_true(selector ~= nil, "subtitle selection should override mpv g-s with a forced sequence")
+selector.fn()
+local selection_call = recorded.async_calls[#recorded.async_calls]
+assert_true(
+	selection_call[3] == '{"actionId":"openSubtitleSelection"}',
+	"subtitle selection should dispatch its session action"
+)
+
+local native_bindings = {}
+function mp.get_property_native(name)
+	assert_true(name == "input-bindings", "only native input bindings should be queried")
+	return native_bindings
+end
+
+for _, case in ipairs({
+	{ key = "g", priority = 1, enabled = false },
+	{ key = "G", priority = 1, enabled = true },
+	{ key = "Shift+g", priority = 1, enabled = true },
+	{ key = "Ctrl+g", priority = 1, enabled = true },
+	{ key = "g", priority = -1, enabled = true },
+	{ key = "g", priority = 1, cmd = "ignore", enabled = true },
+	{ key = "g", priority = 1, cmd = "no-osd ignore", enabled = true },
+}) do
+	native_bindings = { { key = case.key, cmd = case.cmd or "show-text single", priority = case.priority } }
+	recorded.bindings = {}
+	assert_true(bindings.reload_bindings(), "binding reload should succeed")
+	assert_true((find_binding("g-s") ~= nil) == case.enabled, "sequence prefix conflict: " .. case.key)
+end
+assert_true(#recorded.osd > 0, "native prefix conflicts should be visible")
+print("plugin sequence conflict tests: OK")

src/config/definitions.ts

@@ -56,6 +56,7 @@ const { immersionTracking } = IMMERSION_DEFAULT_CONFIG;
 const { stats } = STATS_DEFAULT_CONFIG;
 
 export const DEFAULT_CONFIG: ResolvedConfig = {
+  subtitleSelection: { enabled: false },
   subtitleGeneration: { ...DEFAULT_SUBTITLE_GENERATION_CONFIG },
   subtitlePosition,
   keybindings,

src/config/definitions/defaults-core.ts

@@ -99,6 +99,7 @@ export const CORE_DEFAULT_CONFIG: Pick<
     openRuntimeOptions: 'CommandOrControl+Shift+O',
     openJimaku: 'Ctrl+Shift+J',
     openTsukihime: 'Ctrl+Shift+T',
+    openSubtitleSelection: 'g-s',
     openSubtitleGeneration: 'Ctrl+Shift+G',
     openSessionHelp: 'CommandOrControl+Slash',
     openControllerSelect: 'Alt+C',

src/config/definitions/options-core.ts

@@ -628,6 +628,13 @@ export function buildCoreConfigOptionRegistry(
       defaultValue: defaultConfig.shortcuts.openSessionHelp,
       description: 'Accelerator that opens the session help / keybinding cheatsheet.',
     },
+    {
+      path: 'shortcuts.openSubtitleSelection',
+      kind: 'string',
+      defaultValue: defaultConfig.shortcuts.openSubtitleSelection,
+      description:
+        'Open subtitle selection when enabled. Use g-s to press g then s. Set null to unbind.',
+    },
     {
       path: 'shortcuts.openSubtitleGeneration',
       kind: 'string',

src/config/definitions/options-subtitle.ts

@@ -6,6 +6,13 @@ export function buildSubtitleConfigOptionRegistry(
   defaultConfig: ResolvedConfig,
 ): ConfigOptionRegistryEntry[] {
   return [
+    {
+      path: 'subtitleSelection.enabled',
+      kind: 'boolean',
+      defaultValue: defaultConfig.subtitleSelection.enabled,
+      description:
+        'Use the SubMiner modal to select primary and secondary subtitle tracks. When enabled, its shortcut overrides mpv subtitle selection.',
+    },
     ...(
       ['whisperPath', 'modelPath', 'ffmpegPath', 'ffprobePath', 'vadModelPath', 'vadPath'] as const
     ).map((key) => ({

src/config/definitions/template-sections.ts

@@ -1,6 +1,12 @@
 import { ConfigTemplateSection } from './shared';
 
 const CORE_TEMPLATE_SECTIONS: ConfigTemplateSection[] = [
+  {
+    title: 'Subtitle Selection',
+    description: ['Select primary and secondary mpv subtitle tracks from the overlay.'],
+    notes: ['Hot-reload: enabling or disabling updates the session shortcut immediately.'],
+    key: 'subtitleSelection',
+  },
   {
     title: 'Japanese Subtitle Generation',
     description: [

src/config/hot-reload.ts

@@ -2,7 +2,13 @@ function pathStartsWith(path: string, prefix: string): boolean {
   return path === prefix || path.startsWith(`${prefix}.`);
 }
 
-const HOT_RELOAD_ROOTS = ['subtitleStyle', 'keybindings', 'shortcuts', 'subtitleSidebar'] as const;
+const HOT_RELOAD_ROOTS = [
+  'subtitleStyle',
+  'keybindings',
+  'shortcuts',
+  'subtitleSidebar',
+  'subtitleSelection',
+] as const;
 
 const HOT_RELOAD_EXACT_OR_PREFIX_PATHS = [
   'secondarySub.defaultMode',

src/config/resolve/core-domains.ts

@@ -6,6 +6,25 @@ import { asBoolean, asNumber, asString, isObject } from './shared';
 export function applyCoreDomainConfig(context: ResolveContext): void {
   const { src, resolved, warn } = context;
 
+  if (isObject(src.subtitleSelection)) {
+    const enabled = asBoolean(src.subtitleSelection.enabled);
+    if (enabled !== undefined) resolved.subtitleSelection.enabled = enabled;
+    else if (src.subtitleSelection.enabled !== undefined)
+      warn(
+        'subtitleSelection.enabled',
+        src.subtitleSelection.enabled,
+        resolved.subtitleSelection.enabled,
+        'Expected boolean.',
+      );
+  } else if (src.subtitleSelection !== undefined) {
+    warn(
+      'subtitleSelection',
+      src.subtitleSelection,
+      resolved.subtitleSelection,
+      'Expected object.',
+    );
+  }
+
   if (isObject(src.texthooker)) {
     const launchAtStartup = asBoolean(src.texthooker.launchAtStartup);
     if (launchAtStartup !== undefined) {
@@ -237,6 +256,7 @@ export function applyCoreDomainConfig(context: ResolveContext): void {
       'openRuntimeOptions',
       'openJimaku',
       'openTsukihime',
+      'openSubtitleSelection',
       'openSubtitleGeneration',
       'openSessionHelp',
       'openControllerSelect',

src/config/resolve/subtitle-selection.test.ts

@@ -0,0 +1,63 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { resolveConfig } from '../resolve';
+import { DEFAULT_CONFIG } from '../definitions';
+import { buildConfigSettingsRegistry } from '../settings/registry';
+import { resolveConfiguredShortcuts } from '../../core/utils/shortcut-config';
+import {
+  compileSessionBindings,
+  buildPluginSessionBindingsArtifact,
+} from '../../core/services/session-bindings';
+
+function bindings(config: ReturnType<typeof resolveConfig>['resolved']) {
+  return compileSessionBindings({
+    shortcuts: resolveConfiguredShortcuts(config, DEFAULT_CONFIG),
+    keybindings: config.keybindings,
+    platform: 'linux',
+  });
+}
+
+test('subtitle selection is opt-in and enabling it compiles g-s for mpv and the overlay', () => {
+  const defaults = resolveConfig({}).resolved;
+  assert.equal(defaults.subtitleSelection.enabled, false);
+  assert.equal(defaults.shortcuts.openSubtitleSelection, 'g-s');
+  const find = (config: typeof defaults) =>
+    bindings(config).bindings.find(
+      (binding) =>
+        binding.actionType === 'session-action' && binding.actionId === 'openSubtitleSelection',
+    );
+  assert.equal(find(defaults), undefined);
+  const enabled = resolveConfig({ subtitleSelection: { enabled: true } }).resolved;
+  const binding = find(enabled);
+  assert.ok(binding);
+  assert.deepEqual(binding.key, { code: 'KeyG-KeyS', modifiers: [] });
+  assert.equal(bindings(enabled).warnings.length, 0);
+  const artifact = buildPluginSessionBindingsArtifact({
+    bindings: [binding],
+    warnings: [],
+    numericSelectionTimeoutMs: 1000,
+  });
+  assert.deepEqual(artifact.bindings[0], {
+    ...binding,
+    cliArgs: ['--session-action', '{"actionId":"openSubtitleSelection"}'],
+  });
+  enabled.subtitleSelection.enabled = false;
+  assert.equal(find(enabled), undefined);
+});
+
+test('subtitle selection settings are validated, hot reloadable, and the shortcut can be cleared', () => {
+  // @ts-expect-error Config files can contain invalid values at runtime.
+  const { resolved, warnings } = resolveConfig({ subtitleSelection: { enabled: 'yes' } });
+  assert.equal(resolved.subtitleSelection.enabled, false);
+  assert.equal(warnings.length, 1);
+  const field = buildConfigSettingsRegistry(resolved).find(
+    (entry) => entry.configPath === 'subtitleSelection.enabled',
+  );
+  assert.equal(field?.category, 'behavior');
+  assert.equal(field?.restartBehavior, 'hot-reload');
+  const cleared = resolveConfig({
+    subtitleSelection: { enabled: true },
+    shortcuts: { openSubtitleSelection: null },
+  }).resolved;
+  assert.equal(resolveConfiguredShortcuts(cleared, DEFAULT_CONFIG).openSubtitleSelection, null);
+});

src/config/settings/registry.ts

@@ -455,6 +455,9 @@ function categoryAndSection(path: string): { category: ConfigSettingsCategory; s
   if (path.startsWith('subsync.')) {
     return { category: 'integrations', section: topSection(path) };
   }
+  if (path.startsWith('subtitleSelection.')) {
+    return { category: 'behavior', section: 'Subtitle Selection' };
+  }
   if (path.startsWith('subtitleGeneration.')) {
     return { category: 'integrations', section: 'Japanese Subtitle Generation' };
   }
@@ -631,6 +634,7 @@ function subsectionForPath(path: string): string | undefined {
       leaf === 'openRuntimeOptions' ||
       leaf === 'openJimaku' ||
       leaf === 'openTsukihime' ||
+      leaf === 'openSubtitleSelection' ||
       leaf === 'openSubtitleGeneration' ||
       leaf === 'openSessionHelp' ||
       leaf === 'openControllerSelect' ||

src/core/services/ipc.ts

@@ -93,7 +93,7 @@ export interface IpcServiceDeps {
   handleMpvCommand: (command: Array<string | number>) => void;
   getKeybindings: () => unknown;
   getMpvInputBindings?: () => Promise<MpvInputBindingsSnapshot>;
-  getSessionBindings?: () => CompiledSessionBinding[];
+  getSessionBindings?: () => CompiledSessionBinding[] | Promise<CompiledSessionBinding[]>;
   getConfiguredShortcuts: () => unknown;
   dispatchSessionAction?: (request: SessionActionDispatchRequest) => void | Promise<void>;
   getStatsToggleKey: () => string;
@@ -378,7 +378,7 @@ export interface IpcDepsRuntimeOptions {
   handleMpvCommand: (command: Array<string | number>) => void;
   getKeybindings: () => unknown;
   getMpvInputBindings?: () => Promise<MpvInputBindingsSnapshot>;
-  getSessionBindings?: () => CompiledSessionBinding[];
+  getSessionBindings?: () => CompiledSessionBinding[] | Promise<CompiledSessionBinding[]>;
   getConfiguredShortcuts: () => unknown;
   dispatchSessionAction?: (request: SessionActionDispatchRequest) => void | Promise<void>;
   getStatsToggleKey: () => string;

src/core/services/overlay-shortcut-handler.test.ts

@@ -29,6 +29,7 @@ function makeShortcuts(overrides: Partial<ConfiguredShortcuts> = {}): Configured
     openRuntimeOptions: null,
     openJimaku: null,
     openTsukihime: null,
+    openSubtitleSelection: null,
     openSubtitleGeneration: null,
     openSessionHelp: null,
     openControllerSelect: null,

src/core/services/overlay-shortcut.test.ts

@@ -24,6 +24,7 @@ function createShortcuts(overrides: Partial<ConfiguredShortcuts> = {}): Configur
     openRuntimeOptions: null,
     openJimaku: null,
     openTsukihime: null,
+    openSubtitleSelection: null,
     openSubtitleGeneration: null,
     openSessionHelp: null,
     openControllerSelect: null,

src/core/services/session-actions.test.ts

@@ -43,6 +43,7 @@ function createDeps(overrides: Partial<SessionActionExecutorDeps> = {}) {
     openControllerDebug: () => calls.push('controller-debug'),
     openJimaku: () => calls.push('jimaku'),
     openTsukihime: () => calls.push('tsukihime'),
+    openSubtitleSelection: () => calls.push('subtitle-selection'),
     openSubtitleGeneration: () => calls.push('subtitle-generation'),
     openYoutubeTrackPicker: () => {
       calls.push('youtube');

src/core/services/session-actions.ts

@@ -25,6 +25,7 @@ export interface SessionActionExecutorDeps {
   openControllerDebug: () => void;
   openJimaku: () => void;
   openTsukihime: () => void;
+  openSubtitleSelection: () => void;
   openSubtitleGeneration: () => void;
   openYoutubeTrackPicker: () => void | Promise<void>;
   openPlaylistBrowser: () => boolean | void | Promise<boolean | void>;
@@ -120,6 +121,9 @@ export async function dispatchSessionAction(
     case 'openTsukihime':
       deps.openTsukihime();
       return;
+    case 'openSubtitleSelection':
+      deps.openSubtitleSelection();
+      return;
     case 'openSubtitleGeneration':
       deps.openSubtitleGeneration();
       return;

src/core/services/session-bindings.test.ts

@@ -24,6 +24,7 @@ function createShortcuts(overrides: Partial<ConfiguredShortcuts> = {}): Configur
     openRuntimeOptions: null,
     openJimaku: null,
     openTsukihime: null,
+    openSubtitleSelection: null,
     openSubtitleGeneration: null,
     openSessionHelp: null,
     openControllerSelect: null,
@@ -707,3 +708,58 @@ test('buildPluginSessionBindingsArtifact preserves plugin selector CLI for no-co
   assert.equal(byActionId.get('copySubtitleMultiple')?.cliArgs, undefined);
   assert.equal(byActionId.get('mineSentenceMultiple')?.cliArgs, undefined);
 });
+
+test('single keys reserve sequence prefixes without reserving the second stroke', () => {
+  for (const key of ['g', 'Ctrl+g', 's']) {
+    const result = compileSessionBindings({
+      shortcuts: createShortcuts({ openSubtitleSelection: 'g-s' }),
+      keybindings: [createKeybinding(key, ['show-text', 'single'])],
+      platform: 'linux',
+    });
+    assert.ok(result.bindings.some((binding) => binding.originalKey === key));
+    assert.equal(
+      result.bindings.some((binding) => binding.originalKey === 'g-s'),
+      key !== 'g',
+    );
+    assert.equal(result.warnings.length, key === 'g' ? 1 : 0);
+    if (key === 'g') assert.match(result.warnings[0]!.message, /Single-key bindings take priority/);
+  }
+});
+
+test('configured shortcuts and built-in overlay keys also reserve sequence prefixes', () => {
+  for (const prefix of ['g', 'y', 'v']) {
+    const result = compileSessionBindings({
+      shortcuts: createShortcuts({ openSubtitleSelection: `${prefix}-s`, copySubtitle: 'g' }),
+      keybindings: [],
+      platform: 'linux',
+    });
+    assert.equal(
+      result.bindings.some((binding) => binding.originalKey === `${prefix}-s`),
+      false,
+    );
+    assert.ok(result.bindings.some((binding) => binding.originalKey === 'g'));
+    assert.equal(result.warnings.length, 1);
+  }
+});
+
+test('sequence reservations follow the sidebar code and literal Shift semantics', () => {
+  for (const [toggleKey, disabled] of [
+    ['KeyG', true],
+    ['g', false],
+    ['G', true],
+  ] as const) {
+    const result = compileSessionBindings({
+      shortcuts: createShortcuts({ openSubtitleSelection: 'Shift+g-s' }),
+      keybindings: [],
+      platform: 'linux',
+      rawConfig: {
+        ...DEFAULT_CONFIG,
+        subtitleSidebar: { ...DEFAULT_CONFIG.subtitleSidebar, toggleKey },
+      },
+    });
+    assert.equal(
+      result.bindings.some((binding) => binding.originalKey === 'Shift+g-s'),
+      !disabled,
+    );
+  }
+});

src/core/services/session-bindings.ts

@@ -12,6 +12,10 @@ import type {
   SessionKeySpec,
 } from '../../types/session-bindings';
 import { SPECIAL_COMMANDS } from '../../config';
+import {
+  resolveSessionSequenceConflicts,
+  type SessionKeyReservation,
+} from '../../shared/session-key-sequences';
 
 type PlatformKeyModel = 'darwin' | 'win32' | 'linux';
 
@@ -56,6 +60,7 @@ const SESSION_SHORTCUT_ACTIONS: Array<{
   { key: 'openRuntimeOptions', actionId: 'openRuntimeOptions' },
   { key: 'openJimaku', actionId: 'openJimaku' },
   { key: 'openTsukihime', actionId: 'openTsukihime' },
+  { key: 'openSubtitleSelection', actionId: 'openSubtitleSelection' },
   { key: 'openSubtitleGeneration', actionId: 'openSubtitleGeneration' },
   { key: 'openSessionHelp', actionId: 'openSessionHelp' },
   { key: 'openControllerSelect', actionId: 'openControllerSelect' },
@@ -81,6 +86,13 @@ function normalizeCodeToken(
 ): string | null {
   const normalized = token.trim();
   if (!normalized) return null;
+  // Two lowercase letters use mpv's sequential-key syntax, for example g-s.
+  if (/^[a-z]-[a-z]$/.test(normalized)) {
+    return normalized
+      .split('-')
+      .map((letter) => `Key${letter.toUpperCase()}`)
+      .join('-');
+  }
   if (options.allowMouseButtons === true) {
     const normalizedMouse = normalized.toUpperCase();
     if (MPV_MOUSE_BUTTON_CODES.has(normalizedMouse)) {
@@ -543,7 +555,37 @@ export function compileSessionBindings(input: CompileSessionBindingsInput): {
   }
 
   bindings.sort((left, right) => left.sourcePath.localeCompare(right.sourcePath));
-  return { bindings, warnings };
+  const reservations: SessionKeyReservation[] = [
+    { key: { code: 'KeyY', modifiers: [] }, path: 'built-in y sequences' },
+    { key: { code: 'KeyV', modifiers: [] }, path: 'primary subtitle visibility key' },
+    { key: { code: 'KeyY', modifiers: ['ctrl'] }, path: 'lookup window toggle' },
+    { key: { code: 'KeyY', modifiers: ['meta'] }, path: 'lookup window toggle' },
+    { key: { code: 'KeyY', modifiers: ['ctrl', 'shift'] }, path: 'keyboard-driven mode toggle' },
+    { key: { code: 'KeyY', modifiers: ['shift', 'meta'] }, path: 'keyboard-driven mode toggle' },
+    ...[...candidates.values()].flatMap((drafts) =>
+      drafts.map(({ binding }) => ({
+        key: binding.key,
+        path: binding.sourcePath,
+      })),
+    ),
+  ];
+  const sidebarKey = input.rawConfig?.subtitleSidebar?.toggleKey;
+  if (sidebarKey) {
+    const { key } = parseSessionBindingKey(sidebarKey, input.platform);
+    if (key) {
+      // The sidebar accepts DOM codes with either Shift state, or literal characters.
+      if (/^[A-Z]$/.test(sidebarKey)) key.modifiers = ['shift'];
+      reservations.push({ key, path: 'subtitleSidebar.toggleKey' });
+      if (/^Key[A-Z]$/.test(sidebarKey)) {
+        reservations.push({
+          key: { ...key, modifiers: ['shift'] },
+          path: 'subtitleSidebar.toggleKey',
+        });
+      }
+    }
+  }
+  const result = resolveSessionSequenceConflicts(bindings, reservations);
+  return { bindings: result.bindings, warnings: [...warnings, ...result.warnings] };
 }
 
 export function buildPluginSessionBindingsArtifact(input: {

src/core/utils/shortcut-config.ts

@@ -16,6 +16,7 @@ export interface ConfiguredShortcuts {
   openRuntimeOptions: string | null | undefined;
   openJimaku: string | null | undefined;
   openTsukihime: string | null | undefined;
+  openSubtitleSelection: string | null | undefined;
   openSubtitleGeneration: string | null | undefined;
   openSessionHelp: string | null | undefined;
   openControllerSelect: string | null | undefined;
@@ -68,6 +69,10 @@ export function resolveConfiguredShortcuts(
     openRuntimeOptions: normalizeShortcut(shortcutValue('openRuntimeOptions')),
     openJimaku: normalizeShortcut(shortcutValue('openJimaku')),
     openTsukihime: normalizeShortcut(shortcutValue('openTsukihime')),
+    openSubtitleSelection:
+      config.subtitleSelection?.enabled === true
+        ? normalizeShortcut(shortcutValue('openSubtitleSelection'))
+        : null,
     openSubtitleGeneration: normalizeShortcut(shortcutValue('openSubtitleGeneration')),
     openSessionHelp: normalizeShortcut(shortcutValue('openSessionHelp')),
     openControllerSelect: normalizeShortcut(shortcutValue('openControllerSelect')),

src/main.ts

@@ -466,6 +466,11 @@ import { handleMpvCommandFromIpcRuntime } from './main/ipc-mpv-command';
 import { registerIpcRuntimeServices } from './main/ipc-runtime';
 import { createSubtitleGenerationRuntime } from './main/runtime/subtitle-generation-runtime';
 import { registerSubtitleGenerationIpc } from './main/runtime/subtitle-generation-ipc';
+import {
+  createSubtitleSelectionRuntime,
+  openSubtitleSelectionModal,
+  registerSubtitleSelectionIpc,
+} from './main/runtime/subtitle-selection';
 import { openSubtitleGenerationModal } from './main/runtime/subtitle-generation-open';
 import { createAnkiJimakuIpcRuntimeServiceDeps } from './main/dependencies';
 import { createMainBootServices, type MainBootServicesResult } from './main/boot/services';
@@ -4583,6 +4588,7 @@ const {
       maybeStartOverlayLoadingOsd();
       flushQueuedMpvOsdNotifications();
       secondarySubtitleTrackController.scheduleRefresh(0);
+      void refreshMpvSessionBindings();
       if (appState.sessionBindingsInitialized) {
         sendMpvCommandRuntime(appState.mpvClient, [
           'script-message',
@@ -5235,20 +5241,32 @@ const {
   },
 });
 
-const { persistSessionBindings, refreshCurrentSessionBindings } = createSessionBindingsRuntime({
-  configDir: CONFIG_DIR,
-  getKeybindings: () => appState.keybindings,
-  getConfiguredShortcuts: () => getConfiguredShortcuts(),
-  getResolvedConfig: () => configService.getConfig(),
-  getMpvClient: () => appState.mpvClient,
-  setSessionBindings: (bindings) => {
-    appState.sessionBindings = bindings;
-  },
-  setSessionBindingsInitialized: (initialized) => {
-    appState.sessionBindingsInitialized = initialized;
-  },
-  logWarn: (message) => logger.warn(message),
-});
+const { persistSessionBindings, refreshCurrentSessionBindings, refreshMpvSessionBindings } =
+  createSessionBindingsRuntime({
+    configDir: CONFIG_DIR,
+    getKeybindings: () => appState.keybindings,
+    getConfiguredShortcuts: () => getConfiguredShortcuts(),
+    getResolvedConfig: () => configService.getConfig(),
+    getMpvClient: () => appState.mpvClient,
+    setSessionBindings: (bindings) => {
+      appState.sessionBindings = bindings;
+    },
+    setSessionBindingsInitialized: (initialized) => {
+      appState.sessionBindingsInitialized = initialized;
+    },
+    logWarn: (message) => logger.warn(message),
+    onBindingsChanged: (bindings) =>
+      overlayManager.broadcastToOverlayWindows(IPC_CHANNELS.event.sessionBindingsChanged, bindings),
+    onWarning: (warning) => {
+      if (warning.kind !== 'conflict') return;
+      overlayNotificationsRuntime.showOverlayNotification({
+        id: `session-binding-conflict:${warning.path}`,
+        title: 'Shortcut conflict',
+        body: warning.message,
+        variant: 'warning',
+      });
+    },
+  });
 
 const { flushMpvLog, showMpvOsd } = createMpvOsdRuntimeHandlers({
   appendToMpvLogMainDeps: {
@@ -5503,6 +5521,14 @@ async function dispatchSessionAction(request: SessionActionDispatchRequest): Pro
     openJimaku: () => openJimakuOverlay(),
     openTsukihime: () => openTsukihimeOverlay(),
     openSessionHelp: () => openSessionHelpOverlay(),
+    openSubtitleSelection: () => {
+      if (!configService.getConfig().subtitleSelection.enabled) return;
+      openOverlayHostedModalWithOsd(
+        openSubtitleSelectionModal,
+        'Subtitle selection overlay unavailable.',
+        'Failed to open subtitle selection overlay.',
+      );
+    },
     openSubtitleGeneration: () => openSubtitleGenerationOverlay(),
     openCharacterDictionaryManager: () => openCharacterDictionaryManagerOverlay(),
     openControllerSelect: () => openControllerSelectOverlay(),
@@ -5855,8 +5881,9 @@ const { registerIpcRuntimeHandlers } = composeIpcRuntimeHandlers({
       saveSubtitlePosition: (position) => saveSubtitlePosition(position),
       getMecabTokenizer: () => appState.mecabTokenizer,
       getKeybindings: () => appState.keybindings,
-      getMpvInputBindings: () =>
-        readMpvInputBindings({
+      getMpvInputBindings: async () => {
+        await refreshMpvSessionBindings();
+        return readMpvInputBindings({
           getMpvClient: () => appState.mpvClient,
           getConfiguredKeybindings: () => configService.getConfig().keybindings ?? [],
           platform:
@@ -5865,8 +5892,12 @@ const { registerIpcRuntimeHandlers } = composeIpcRuntimeHandlers({
               : process.platform === 'win32'
                 ? 'win32'
                 : 'linux',
-        }),
-      getSessionBindings: () => appState.sessionBindings,
+        });
+      },
+      getSessionBindings: async () => {
+        await refreshMpvSessionBindings();
+        return appState.sessionBindings;
+      },
       getConfiguredShortcuts: () => getConfiguredShortcuts(),
       dispatchSessionAction: (request) => dispatchSessionAction(request),
       getStatsToggleKey: () => configService.getConfig().stats.toggleKey,
@@ -6649,6 +6680,17 @@ function setOverlayVisible(visible: boolean): void {
 }
 
 registerIpcRuntimeHandlers();
+registerSubtitleSelectionIpc({
+  ipc: ipcMain,
+  isAllowedSender: (sender) =>
+    [overlayManager.getMainWindow(), overlayManager.getModalWindow()].some(
+      (window) => window && !window.isDestroyed() && window.webContents === sender,
+    ),
+  runtime: createSubtitleSelectionRuntime({
+    isEnabled: () => configService.getConfig().subtitleSelection.enabled,
+    getMpvClient: () => appState.mpvClient,
+  }),
+});
 const subtitleGenerationRuntime = createSubtitleGenerationRuntime({
   getConfig: () => configService.getConfig().subtitleGeneration,
   getModelDirectory: () =>

src/main/runtime/config-hot-reload-handlers.ts

@@ -163,7 +163,10 @@ export function createConfigHotReloadAppliedHandler(deps: ConfigHotReloadApplied
     deps.setKeybindings(payload.keybindings);
     deps.setSessionBindings(payload.sessionBindings, payload.sessionBindingWarnings);
 
-    if (diff.hotReloadFields.includes('shortcuts')) {
+    if (
+      diff.hotReloadFields.includes('shortcuts') ||
+      diff.hotReloadFields.includes('subtitleSelection')
+    ) {
       deps.refreshGlobalAndOverlayShortcuts();
     }
 

src/main/runtime/global-shortcuts-runtime-handlers.test.ts

@@ -20,6 +20,7 @@ function createShortcuts(): ConfiguredShortcuts {
     openRuntimeOptions: null,
     openJimaku: null,
     openTsukihime: null,
+    openSubtitleSelection: null,
     openSubtitleGeneration: null,
     openSessionHelp: null,
     openControllerSelect: null,

src/main/runtime/global-shortcuts.test.ts

@@ -24,6 +24,7 @@ function createShortcuts(): ConfiguredShortcuts {
     openRuntimeOptions: null,
     openJimaku: null,
     openTsukihime: null,
+    openSubtitleSelection: null,
     openSubtitleGeneration: null,
     openSessionHelp: null,
     openControllerSelect: null,

src/main/runtime/session-bindings-runtime.test.ts

@@ -70,3 +70,69 @@ test('persistSessionBindings keeps saved bindings when mpv reload notification f
     fs.rmSync(root, { recursive: true, force: true });
   }
 });
+
+test('native prefix conflicts publish the same effective bindings to the overlay and plugin and recover', async () => {
+  const root = fs.mkdtempSync(path.join(os.tmpdir(), 'subminer-session-conflict-'));
+  const sequence: CompiledSessionBinding = {
+    sourcePath: 'shortcuts.openSubtitleSelection',
+    originalKey: 'g-s',
+    key: { code: 'KeyG-KeyS', modifiers: [] },
+    actionType: 'session-action',
+    actionId: 'openSubtitleSelection',
+  };
+  let nativeKeys: unknown = [];
+  let failDiscovery = false;
+  let published: CompiledSessionBinding[] = [];
+  const events: CompiledSessionBinding[][] = [];
+  const warnings: string[] = [];
+  const client = {
+    connected: true,
+    send: () => {},
+    requestProperty: async () => {
+      if (failDiscovery) throw new Error('temporarily unavailable');
+      return nativeKeys;
+    },
+  };
+  const runtime = createSessionBindingsRuntime({
+    configDir: root,
+    getKeybindings: () => [],
+    getConfiguredShortcuts: () => ({ multiCopyTimeoutMs: 1500 }) as never,
+    getResolvedConfig: () => ({ stats: { toggleKey: 's', markWatchedKey: 'w' } }) as ResolvedConfig,
+    getMpvClient: () => client,
+    setSessionBindings: (bindings) => {
+      published = bindings;
+    },
+    setSessionBindingsInitialized: () => {},
+    logWarn: () => {},
+    onBindingsChanged: (bindings) => events.push(bindings),
+    onWarning: (warning) => warnings.push(warning.message),
+  });
+  const readArtifact = () =>
+    JSON.parse(fs.readFileSync(path.join(root, 'session-bindings.json'), 'utf8'));
+  try {
+    runtime.persistSessionBindings([sequence]);
+    nativeKeys = [{ key: 'g', cmd: 'show-text single', priority: 1 }];
+    await runtime.refreshMpvSessionBindings();
+    assert.deepEqual(published, []);
+    assert.deepEqual(events.at(-1), readArtifact().bindings);
+    assert.equal(warnings.length, 1);
+    assert.match(warnings[0]!, /mpv input binding "g"/);
+    await runtime.refreshMpvSessionBindings();
+    assert.equal(events.length, 2, 'unchanged discovery must not create a reload loop');
+    assert.equal(warnings.length, 1);
+    failDiscovery = true;
+    await runtime.refreshMpvSessionBindings();
+    assert.deepEqual(published, [], 'failed discovery retains the known conflict');
+    failDiscovery = false;
+    nativeKeys = [{ key: 'Shift+g', cmd: 'show-text shifted', priority: 1 }];
+    await runtime.refreshMpvSessionBindings();
+    assert.deepEqual(published, [sequence]);
+    assert.equal(readArtifact().bindings[0].key.code, 'KeyG-KeyS');
+    assert.deepEqual(readArtifact().warnings, []);
+    client.connected = false;
+    await runtime.refreshMpvSessionBindings();
+    assert.deepEqual(published, [sequence]);
+  } finally {
+    fs.rmSync(root, { recursive: true, force: true });
+  }
+});

src/main/runtime/session-bindings-runtime.ts

@@ -6,16 +6,26 @@ import {
 import type { ConfiguredShortcuts } from '../../core/utils/shortcut-config';
 import type { CompiledSessionBinding, Keybinding, ResolvedConfig } from '../../types';
 import { writeSessionBindingsArtifact } from './session-bindings-artifact';
+import { parseMpvInputBindingKeys } from '../../shared/mpv-input-bindings';
+import {
+  reserveMpvSequencePrefixes,
+  resolveSessionSequenceConflicts,
+} from '../../shared/session-key-sequences';
+import type { SessionBindingWarning } from '../../types/session-bindings';
 
 export interface SessionBindingsRuntimeDeps {
   configDir: string;
   getKeybindings: () => Keybinding[];
   getConfiguredShortcuts: () => ConfiguredShortcuts;
   getResolvedConfig: () => ResolvedConfig;
-  getMpvClient: () => MpvRuntimeClientLike | null;
+  getMpvClient: () =>
+    | (MpvRuntimeClientLike & { requestProperty: (name: string) => Promise<unknown> })
+    | null;
   setSessionBindings: (bindings: CompiledSessionBinding[]) => void;
   setSessionBindingsInitialized: (initialized: boolean) => void;
   logWarn: (message: string, details?: unknown) => void;
+  onBindingsChanged?: (bindings: CompiledSessionBinding[]) => void;
+  onWarning?: (warning: SessionBindingWarning) => void;
 }
 
 export function createSessionBindingsRuntime(deps: SessionBindingsRuntimeDeps): {
@@ -24,7 +34,20 @@ export function createSessionBindingsRuntime(deps: SessionBindingsRuntimeDeps):
     warnings?: ReturnType<typeof compileSessionBindings>['warnings'],
   ) => void;
   refreshCurrentSessionBindings: () => void;
+  refreshMpvSessionBindings: () => Promise<void>;
 } {
+  let sourceBindings: CompiledSessionBinding[] = [];
+  let sourceWarnings: SessionBindingWarning[] = [];
+  let nativeSnapshot: {
+    client: ReturnType<SessionBindingsRuntimeDeps['getMpvClient']>;
+    keys: string[];
+  } | null = null;
+  let pending: {
+    client: ReturnType<SessionBindingsRuntimeDeps['getMpvClient']>;
+    promise: Promise<void>;
+  } | null = null;
+  let publishedSignature: string | null = null;
+  let reportedWarnings = new Set<string>();
   function resolveSessionBindingPlatform(): 'darwin' | 'win32' | 'linux' {
     if (process.platform === 'darwin') return 'darwin';
     if (process.platform === 'win32') return 'win32';
@@ -49,8 +72,27 @@ export function createSessionBindingsRuntime(deps: SessionBindingsRuntimeDeps):
     bindings: CompiledSessionBinding[],
     warnings: ReturnType<typeof compileSessionBindings>['warnings'] = [],
   ): void {
+    sourceBindings = bindings;
+    sourceWarnings = warnings;
+    publishBindings();
+  }
+
+  function publishBindings(): void {
+    const client = deps.getMpvClient();
+    const keys = client?.connected && nativeSnapshot?.client === client ? nativeSnapshot.keys : [];
+    const result = resolveSessionSequenceConflicts(
+      sourceBindings,
+      reserveMpvSequencePrefixes(keys),
+    );
+    const warnings = [...sourceWarnings, ...result.warnings];
+    const signature = JSON.stringify([
+      result.bindings,
+      warnings,
+      deps.getConfiguredShortcuts().multiCopyTimeoutMs,
+    ]);
+    if (signature === publishedSignature) return;
     const artifact = buildPluginSessionBindingsArtifact({
-      bindings,
+      bindings: result.bindings,
       warnings,
       numericSelectionTimeoutMs: deps.getConfiguredShortcuts().multiCopyTimeoutMs,
     });
@@ -60,8 +102,16 @@ export function createSessionBindingsRuntime(deps: SessionBindingsRuntimeDeps):
       deps.logWarn('[session-bindings] Failed to write session bindings artifact');
       throw error;
     }
-    deps.setSessionBindings(bindings);
+    publishedSignature = signature;
+    deps.setSessionBindings(result.bindings);
     deps.setSessionBindingsInitialized(true);
+    const nextWarnings = new Set(warnings.map((warning) => warning.message));
+    for (const warning of warnings) {
+      if (reportedWarnings.has(warning.message)) continue;
+      deps.logWarn(`[session-bindings] ${warning.message}`);
+      deps.onWarning?.(warning);
+    }
+    reportedWarnings = nextWarnings;
     const mpvClient = deps.getMpvClient();
     if (mpvClient?.connected) {
       try {
@@ -70,15 +120,41 @@ export function createSessionBindingsRuntime(deps: SessionBindingsRuntimeDeps):
         deps.logWarn('[session-bindings] Failed to notify mpv to reload session bindings', error);
       }
     }
+    deps.onBindingsChanged?.(result.bindings);
+  }
+
+  async function refreshMpvSessionBindings(): Promise<void> {
+    const client = deps.getMpvClient();
+    if (!client?.connected) {
+      nativeSnapshot = null;
+      publishBindings();
+      return;
+    }
+    if (pending?.client === client) return pending.promise;
+    const promise = (async () => {
+      try {
+        const raw = await client.requestProperty('input-bindings');
+        if (client !== deps.getMpvClient() || !client.connected) return;
+        nativeSnapshot = { client, keys: parseMpvInputBindingKeys(raw, { includeIgnored: false }) };
+        publishBindings();
+      } catch {
+        // Keep the last successful snapshot if discovery is temporarily unavailable.
+      }
+    })();
+    const request = { client, promise };
+    pending = request;
+    try {
+      await promise;
+    } finally {
+      if (pending === request) pending = null;
+    }
   }
 
   function refreshCurrentSessionBindings(): void {
     const compiled = compileCurrentSessionBindings();
-    for (const warning of compiled.warnings) {
-      deps.logWarn(`[session-bindings] ${warning.message}`);
-    }
     persistSessionBindings(compiled.bindings, compiled.warnings);
+    void refreshMpvSessionBindings();
   }
 
-  return { persistSessionBindings, refreshCurrentSessionBindings };
+  return { persistSessionBindings, refreshCurrentSessionBindings, refreshMpvSessionBindings };
 }

src/main/runtime/subtitle-selection.test.ts

@@ -0,0 +1,101 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { createSubtitleSelectionRuntime } from './subtitle-selection';
+
+function setup() {
+  let enabled = true;
+  const properties = new Map<string, unknown>([
+    ['path', '/video.mkv'],
+    [
+      'track-list',
+      [
+        { id: 1, type: 'audio' },
+        { id: 2, type: 'sub', title: 'Japanese', lang: 'ja', codec: 'ass' },
+        { id: 3, type: 'sub', title: 'English', lang: 'en', external: true },
+        { id: '4', type: 'sub' },
+      ],
+    ],
+    ['sid', 2],
+    ['secondary-sid', 3],
+  ]);
+  const commands: unknown[][] = [];
+  const client = {
+    connected: true,
+    requestProperty: async (name: string) => properties.get(name),
+    request: async (command: unknown[]) => {
+      commands.push(command);
+      return { error: 'success' };
+    },
+  };
+  const runtime = createSubtitleSelectionRuntime({
+    isEnabled: () => enabled,
+    getMpvClient: () => client,
+  });
+  return {
+    runtime,
+    properties,
+    commands,
+    client,
+    disable: () => {
+      enabled = false;
+    },
+  };
+}
+
+test('subtitle selector lists only valid subtitle tracks and current selections', async () => {
+  const { runtime, properties } = setup();
+  assert.deepEqual(await runtime.getState(), {
+    mediaPath: '/video.mkv',
+    primary: 2,
+    secondary: 3,
+    tracks: [
+      { id: 2, label: '#2 · Japanese · ja · ass' },
+      { id: 3, label: '#3 · English · en · external' },
+    ],
+  });
+  properties.set('sid', 'no');
+  properties.set('secondary-sid', false);
+  const state = await runtime.getState();
+  assert.equal(state.primary, null);
+  assert.equal(state.secondary, null);
+});
+
+test('subtitle selector swaps tracks and supports disabling both tracks', async () => {
+  const { runtime, commands } = setup();
+  await runtime.apply({ mediaPath: '/video.mkv', primary: 3, secondary: 2 });
+  assert.deepEqual(commands, [
+    ['set_property', 'secondary-sid', 'no'],
+    ['set_property', 'sid', 3],
+    ['set_property', 'secondary-sid', 2],
+  ]);
+  commands.length = 0;
+  await runtime.apply({ mediaPath: '/video.mkv', primary: null, secondary: null });
+  assert.ok(commands.every((command) => command[2] === 'no'));
+});
+
+test('subtitle selector rejects stale media, unavailable tracks, duplicate tracks and malformed requests without mutation', async () => {
+  const { runtime, commands } = setup();
+  for (const request of [
+    { mediaPath: '/other.mkv', primary: 2, secondary: 3 },
+    { mediaPath: '/video.mkv', primary: 99, secondary: null },
+    { mediaPath: '/video.mkv', primary: 2, secondary: 2 },
+    { mediaPath: '/video.mkv', primary: '2', secondary: null },
+    { mediaPath: '/video.mkv', primary: -1, secondary: null },
+    null,
+  ])
+    await assert.rejects(runtime.apply(request));
+  assert.deepEqual(commands, []);
+});
+
+test('subtitle selector gates access on config and connection and propagates mpv failures', async () => {
+  const { runtime, client, disable } = setup();
+  client.request = async () => ({ error: 'property unavailable' });
+  await assert.rejects(
+    runtime.apply({ mediaPath: '/video.mkv', primary: 3, secondary: 2 }),
+    /property unavailable/,
+  );
+  client.connected = false;
+  await assert.rejects(runtime.getState(), /Connect to mpv/);
+  disable();
+  await assert.rejects(runtime.getState(), /Enable subtitle selection/);
+});

src/main/runtime/subtitle-selection.ts

@@ -0,0 +1,117 @@
+import type { IpcMain, WebContents } from 'electron';
+import { IPC_CHANNELS } from '../../shared/ipc/contracts';
+import {
+  parseSubtitleSelectionRequest,
+  type SubtitleSelectionState,
+} from '../../shared/subtitle-selection';
+import { openOverlayHostedModal, retryOverlayModalOpen } from './overlay-hosted-modal-open';
+
+interface SelectionMpvClient {
+  connected: boolean;
+  requestProperty: (name: string) => Promise<unknown>;
+  request: (command: unknown[]) => Promise<{ error?: string }>;
+}
+
+export function openSubtitleSelectionModal(
+  deps: Parameters<typeof openOverlayHostedModal>[0] & Parameters<typeof retryOverlayModalOpen>[0],
+): Promise<boolean> {
+  return retryOverlayModalOpen(deps, {
+    modal: 'subtitle-selection',
+    timeoutMs: 1500,
+    retryWarning: 'Subtitle selection modal did not acknowledge opening; retrying.',
+    sendOpen: () =>
+      openOverlayHostedModal(deps, {
+        channel: IPC_CHANNELS.event.subtitleSelectionOpen,
+        modal: 'subtitle-selection',
+        preferModalWindow: true,
+      }),
+  });
+}
+
+export function createSubtitleSelectionRuntime(deps: {
+  isEnabled: () => boolean;
+  getMpvClient: () => SelectionMpvClient | null;
+}) {
+  function getClient(): SelectionMpvClient {
+    if (!deps.isEnabled()) throw new Error('Enable subtitle selection in Settings first.');
+    const client = deps.getMpvClient();
+    if (!client?.connected) throw new Error('Connect to mpv first.');
+    return client;
+  }
+
+  async function readState(client: SelectionMpvClient): Promise<SubtitleSelectionState> {
+    const mediaPath = await client.requestProperty('path');
+    if (typeof mediaPath !== 'string' || !mediaPath) throw new Error('Open a video first.');
+    const [rawTracks, primary, secondary] = await Promise.all([
+      client.requestProperty('track-list'),
+      client.requestProperty('sid'),
+      client.requestProperty('secondary-sid'),
+    ]);
+    const tracks: SubtitleSelectionState['tracks'] = [];
+    const candidates: unknown[] = Array.isArray(rawTracks) ? rawTracks : [];
+    for (const track of candidates) {
+      if (
+        typeof track !== 'object' ||
+        track === null ||
+        !('type' in track) ||
+        track.type !== 'sub' ||
+        !('id' in track) ||
+        typeof track.id !== 'number' ||
+        !Number.isSafeInteger(track.id) ||
+        track.id <= 0
+      )
+        continue;
+      const details = [
+        'title' in track ? track.title : undefined,
+        'lang' in track ? track.lang : undefined,
+        'codec' in track ? track.codec : undefined,
+      ].filter((value): value is string => typeof value === 'string' && value.length > 0);
+      if ('external' in track && track.external === true) details.push('external');
+      tracks.push({ id: track.id, label: `#${track.id} · ${details.join(' · ') || 'Subtitle'}` });
+    }
+    if ((await client.requestProperty('path')) !== mediaPath)
+      throw new Error('The video changed. Reopen subtitle selection.');
+    const selected = (value: unknown): number | null =>
+      tracks.find((track) => track.id === value)?.id ?? null;
+    return { mediaPath, tracks, primary: selected(primary), secondary: selected(secondary) };
+  }
+
+  async function apply(value: unknown): Promise<void> {
+    const selection = parseSubtitleSelectionRequest(value);
+    const client = getClient();
+    const current = await readState(client);
+    if (current.mediaPath !== selection.mediaPath)
+      throw new Error('The video changed. Reopen subtitle selection.');
+    for (const id of [selection.primary, selection.secondary]) {
+      if (id !== null && !current.tracks.some((track) => track.id === id))
+        throw new Error('A selected track is no longer available. Reopen subtitle selection.');
+    }
+    const set = async (property: string, id: number | null): Promise<void> => {
+      const response = await client.request(['set_property', property, id ?? 'no']);
+      if (response.error && response.error !== 'success') throw new Error(response.error);
+    };
+    // Clear secondary first so swapping the two tracks works in mpv.
+    await set('secondary-sid', null);
+    await set('sid', selection.primary);
+    await set('secondary-sid', selection.secondary);
+  }
+
+  return { getState: async () => readState(getClient()), apply };
+}
+
+export function registerSubtitleSelectionIpc(deps: {
+  ipc: Pick<IpcMain, 'handle'>;
+  isAllowedSender: (sender: WebContents) => boolean;
+  runtime: ReturnType<typeof createSubtitleSelectionRuntime>;
+}): void {
+  deps.ipc.handle(IPC_CHANNELS.request.getSubtitleSelection, (event) => {
+    if (!deps.isAllowedSender(event.sender))
+      throw new Error('Subtitle selection requires the overlay.');
+    return deps.runtime.getState();
+  });
+  deps.ipc.handle(IPC_CHANNELS.request.applySubtitleSelection, (event, value: unknown) => {
+    if (!deps.isAllowedSender(event.sender))
+      throw new Error('Subtitle selection requires the overlay.');
+    return deps.runtime.apply(value);
+  });
+}

src/preload.ts

@@ -81,6 +81,7 @@ import { IPC_CHANNELS } from './shared/ipc/contracts';
 import type { SubtitleGenerationProgress } from './shared/subtitle-generation';
 
 const overlayLayer = resolveOverlayLayerFromArgv(process.argv);
+const onSubtitleSelectionOpen = createQueuedIpcListener(IPC_CHANNELS.event.subtitleSelectionOpen);
 const onSubtitleGenerationOpen = createQueuedIpcListener(IPC_CHANNELS.event.subtitleGenerationOpen);
 
 type EmptyListener = () => void;
@@ -463,6 +464,11 @@ const electronAPI: ElectronAPI = {
     ) as Promise<boolean>,
   getSubtitleStyle: (): Promise<SubtitleStyleConfig | null> =>
     ipcRenderer.invoke(IPC_CHANNELS.request.getSubtitleStyle),
+  onSubtitleSelectionOpen,
+  getSubtitleSelection: () => ipcRenderer.invoke(IPC_CHANNELS.request.getSubtitleSelection),
+  applySubtitleSelection: (
+    request: import('./shared/subtitle-selection').SubtitleSelectionRequest,
+  ) => ipcRenderer.invoke(IPC_CHANNELS.request.applySubtitleSelection, request),
   onSubsyncManualOpen: onSubsyncManualOpenEvent,
   runSubsyncManual: (request: SubsyncManualRunRequest): Promise<SubsyncResult> =>
     ipcRenderer.invoke(IPC_CHANNELS.request.runSubsyncManual, request),
@@ -580,6 +586,14 @@ const electronAPI: ElectronAPI = {
   reportOverlayContentBounds: (measurement: OverlayContentMeasurement) => {
     ipcRenderer.send(IPC_CHANNELS.command.reportOverlayContentBounds, measurement);
   },
+  onSessionBindingsChanged: (
+    callback: (bindings: import('./types').CompiledSessionBinding[]) => void,
+  ) => {
+    ipcRenderer.on(
+      IPC_CHANNELS.event.sessionBindingsChanged,
+      (_event, bindings: import('./types').CompiledSessionBinding[]) => callback(bindings),
+    );
+  },
   onConfigHotReload: (callback: (payload: ConfigHotReloadPayload) => void) => {
     ipcRenderer.on(
       IPC_CHANNELS.event.configHotReload,

src/renderer/controller-interaction-blocking.ts

@@ -4,6 +4,7 @@ type ControllerInteractionModalState = {
   jimakuModalOpen: boolean;
   kikuModalOpen: boolean;
   runtimeOptionsModalOpen: boolean;
+  subtitleSelectionModalOpen?: boolean;
   subsyncModalOpen: boolean;
   subtitleGenerationModalOpen?: boolean;
   youtubePickerModalOpen: boolean;
@@ -18,6 +19,7 @@ export function isControllerInteractionBlocked(state: ControllerInteractionModal
     state.jimakuModalOpen ||
     state.kikuModalOpen ||
     state.runtimeOptionsModalOpen ||
+    state.subtitleSelectionModalOpen ||
     state.subsyncModalOpen ||
     Boolean(state.subtitleGenerationModalOpen) ||
     state.youtubePickerModalOpen ||

src/renderer/handlers/keyboard.test.ts

@@ -92,6 +92,7 @@ function createEmptyShortcuts(): ConfiguredShortcuts {
     openRuntimeOptions: null,
     openJimaku: null,
     openTsukihime: null,
+    openSubtitleSelection: null,
     openSubtitleGeneration: null,
     openSessionHelp: null,
     openControllerSelect: null,
@@ -2404,3 +2405,86 @@ test('stalled mpv discovery does not delay configured overlay controls', async (
     testGlobals.restore();
   }
 });
+
+test('session binding: g-s opens subtitle selection only after the complete sequence', async () => {
+  const { handlers, testGlobals } = createKeyboardHandlerHarness();
+  try {
+    await handlers.setupMpvInputForwarding();
+    handlers.updateSessionBindings([
+      {
+        sourcePath: 'shortcuts.openSubtitleSelection',
+        originalKey: 'g-s',
+        key: { code: 'KeyG-KeyS', modifiers: [] },
+        actionType: 'session-action',
+        actionId: 'openSubtitleSelection',
+      },
+    ]);
+    testGlobals.dispatchKeydown({ key: 's', code: 'KeyS' });
+    testGlobals.dispatchKeydown({ key: 'g', code: 'KeyG' });
+    assert.deepEqual(testGlobals.sessionActions, []);
+    testGlobals.dispatchKeydown({ key: 's', code: 'KeyS' });
+    assert.deepEqual(testGlobals.sessionActions, [
+      { actionId: 'openSubtitleSelection', payload: undefined },
+    ]);
+    testGlobals.dispatchKeydown({ key: 'g', code: 'KeyG' });
+    handlers.updateSessionBindings([]);
+    testGlobals.dispatchKeydown({ key: 's', code: 'KeyS' });
+    assert.equal(testGlobals.sessionActions.length, 1);
+  } finally {
+    testGlobals.restore();
+  }
+});
+
+test('single-key actions run immediately even if a conflicting sequence reaches the renderer', async () => {
+  const { handlers, testGlobals } = createKeyboardHandlerHarness();
+  try {
+    await handlers.setupMpvInputForwarding();
+    handlers.updateSessionBindings([
+      {
+        sourcePath: 'sequence',
+        originalKey: 'g-s',
+        key: { code: 'KeyG-KeyS', modifiers: [] },
+        actionType: 'session-action',
+        actionId: 'openSubtitleSelection',
+      },
+      {
+        sourcePath: 'single',
+        originalKey: 'g',
+        key: { code: 'KeyG', modifiers: [] },
+        actionType: 'mpv-command',
+        command: ['show-text', 'single'],
+      },
+    ]);
+    testGlobals.dispatchKeydown({ key: 'g', code: 'KeyG' });
+    assert.deepEqual(testGlobals.mpvCommands, [['show-text', 'single']]);
+    testGlobals.dispatchKeydown({ key: 's', code: 'KeyS' });
+    assert.deepEqual(testGlobals.sessionActions, []);
+  } finally {
+    testGlobals.restore();
+  }
+});
+
+test('an unfinished built-in y chord cannot start a configured sequence', async () => {
+  const { handlers, testGlobals } = createKeyboardHandlerHarness();
+  try {
+    await handlers.setupMpvInputForwarding();
+    handlers.updateSessionBindings([
+      {
+        sourcePath: 'sequence',
+        originalKey: 'g-s',
+        key: { code: 'KeyG-KeyS', modifiers: [] },
+        actionType: 'session-action',
+        actionId: 'openSubtitleSelection',
+      },
+    ]);
+    testGlobals.dispatchKeydown({ key: 'y', code: 'KeyY' });
+    testGlobals.dispatchKeydown({ key: 'g', code: 'KeyG' });
+    testGlobals.dispatchKeydown({ key: 's', code: 'KeyS' });
+    assert.deepEqual(testGlobals.sessionActions, []);
+    testGlobals.dispatchKeydown({ key: 'g', code: 'KeyG' });
+    testGlobals.dispatchKeydown({ key: 's', code: 'KeyS' });
+    assert.equal(testGlobals.sessionActions.length, 1);
+  } finally {
+    testGlobals.restore();
+  }
+});

src/renderer/handlers/keyboard.ts

@@ -15,6 +15,7 @@ export function createKeyboardHandlers(
     handleRuntimeOptionsKeydown: (e: KeyboardEvent) => boolean;
     handleCharacterDictionaryKeydown: (e: KeyboardEvent) => boolean;
     handleSubsyncKeydown: (e: KeyboardEvent) => boolean;
+    handleSubtitleSelectionKeydown?: (e: KeyboardEvent) => boolean;
     handleSubtitleGenerationKeydown?: (e: KeyboardEvent) => boolean;
     handleKikuKeydown: (e: KeyboardEvent) => boolean;
     handleJimakuKeydown: (e: KeyboardEvent) => boolean;
@@ -133,7 +134,10 @@ export function createKeyboardHandlers(
     updateConfiguredShortcuts(shortcuts, statsToggleKey, markWatchedKey);
   }
 
+  let pendingSequence: { prefix: string; expires: number } | null = null;
+
   function updateSessionBindings(bindings: CompiledSessionBinding[]): void {
+    pendingSequence = null;
     ctx.state.sessionBindings = bindings;
     ctx.state.sessionBindingMap = new Map(
       bindings.map((binding) => [keyEventToStringFromBinding(binding), binding]),
@@ -1049,7 +1053,10 @@ export function createKeyboardHandlers(
     window.addEventListener('focus', () => {
       void importedMpvBindings.refresh();
     });
-    window.addEventListener('blur', importedMpvBindings.releaseAll);
+    window.addEventListener('blur', () => {
+      pendingSequence = null;
+      importedMpvBindings.releaseAll();
+    });
     window.addEventListener('beforeunload', () => {
       clearTimeout(lateScriptRefresh);
       importedMpvBindings.dispose();
@@ -1103,6 +1110,13 @@ export function createKeyboardHandlers(
     );
 
     document.addEventListener('keydown', (e: KeyboardEvent) => {
+      const sequence = pendingSequence;
+      pendingSequence = null;
+      if (ctx.state.subtitleSelectionModalOpen) {
+        pendingSequence = null;
+        options.handleSubtitleSelectionKeydown?.(e);
+        return;
+      }
       if (ctx.state.subtitleGenerationModalOpen) {
         options.handleSubtitleGenerationKeydown?.(e);
         return;
@@ -1187,6 +1201,7 @@ export function createKeyboardHandlers(
       }
 
       if (isTextEntryTarget(e.target)) {
+        pendingSequence = null;
         return;
       }
 
@@ -1194,6 +1209,16 @@ export function createKeyboardHandlers(
         return;
       }
 
+      const sequenceKey = keyEventToString(e);
+      if (sequence && !ctx.state.chordPending && Date.now() <= sequence.expires && !e.repeat) {
+        const binding = ctx.state.sessionBindingMap.get(`${sequence.prefix}-${sequenceKey}`);
+        if (binding) {
+          e.preventDefault();
+          dispatchSessionBinding(binding);
+          return;
+        }
+      }
+
       if (isStatsOverlayToggle(e)) {
         e.preventDefault();
         window.electronAPI.toggleStatsOverlay();
@@ -1276,6 +1301,16 @@ export function createKeyboardHandlers(
         dispatchSessionBinding(binding);
         return;
       }
+      if (
+        !e.repeat &&
+        ctx.state.sessionBindings.some((binding) =>
+          keyEventToStringFromBinding(binding).startsWith(`${sequenceKey}-`),
+        )
+      ) {
+        pendingSequence = { prefix: sequenceKey, expires: Date.now() + 1000 };
+        e.preventDefault();
+        return;
+      }
       if (
         keyboardConfigLoaded &&
         !ctx.state.playlistBrowserModalOpen &&

src/renderer/index.html

@@ -833,6 +833,43 @@
           </div>
         </div>
       </div>
+      <div id="subtitleSelectionModal" class="modal hidden" aria-hidden="true">
+        <div
+          class="modal-content subsync-modal-content"
+          role="dialog"
+          aria-modal="true"
+          aria-labelledby="subtitleSelectionTitle"
+        >
+          <div class="modal-header">
+            <h2 id="subtitleSelectionTitle">Select subtitles</h2>
+            <button id="subtitleSelectionClose" class="modal-close" type="button">Close</button>
+          </div>
+          <div class="modal-body">
+            <div class="subsync-form">
+              <label class="subsync-field">
+                <span>Primary subtitle</span>
+                <select id="subtitleSelectionPrimary"></select>
+              </label>
+              <label class="subsync-field">
+                <span>Secondary subtitle</span>
+                <select id="subtitleSelectionSecondary"></select>
+              </label>
+            </div>
+            <div
+              id="subtitleSelectionStatus"
+              class="runtime-options-status"
+              role="status"
+              aria-live="polite"
+            ></div>
+            <div class="subsync-footer">
+              <button id="subtitleSelectionApply" class="kiku-confirm-button" type="button">
+                Apply
+              </button>
+            </div>
+          </div>
+        </div>
+      </div>
+
       <div id="subsyncModal" class="modal hidden" aria-hidden="true">
         <div class="modal-content subsync-modal-content">
           <div class="modal-header">

src/renderer/modals/session-help-sections.ts

@@ -225,6 +225,8 @@ function describeSessionAction(
       return 'Open jimaku';
     case 'openTsukihime':
       return 'Open TsukiHime';
+    case 'openSubtitleSelection':
+      return 'Select subtitle tracks';
     case 'openSubtitleGeneration':
       return 'Generate Japanese subtitles';
     case 'openYoutubePicker':
@@ -268,6 +270,7 @@ function sectionForSessionBinding(binding: CompiledSessionBinding): string {
     case 'openJimaku':
     case 'openTsukihime':
     case 'openCharacterDictionaryManager':
+    case 'openSubtitleSelection':
     case 'openSubtitleGeneration':
     case 'openControllerSelect':
     case 'openControllerDebug':

src/renderer/modals/subtitle-selection.ts

@@ -0,0 +1,172 @@
+import type { SubtitleSelectionState } from '../../shared/subtitle-selection';
+import type { RendererContext } from '../context';
+import { syncOverlayMouseIgnoreState } from '../overlay-mouse-ignore';
+import { createModalFocusGuard } from './modal-focus-guard';
+
+function element<T extends HTMLElement>(id: string, constructor: new () => T): T {
+  const node = document.getElementById(id);
+  if (!(node instanceof constructor)) throw new Error(`Missing subtitle selection element: ${id}`);
+  return node;
+}
+
+export function createSubtitleSelectionModal(
+  ctx: RendererContext,
+  options: { syncSettingsModalSubtitleSuppression: () => void },
+) {
+  const dom = {
+    modal: element('subtitleSelectionModal', HTMLDivElement),
+    primary: element('subtitleSelectionPrimary', HTMLSelectElement),
+    secondary: element('subtitleSelectionSecondary', HTMLSelectElement),
+    status: element('subtitleSelectionStatus', HTMLDivElement),
+    apply: element('subtitleSelectionApply', HTMLButtonElement),
+    close: element('subtitleSelectionClose', HTMLButtonElement),
+  };
+  let snapshot: SubtitleSelectionState | null = null;
+  let generation = 0;
+  let pending = false;
+  let priorFocus: Element | null = null;
+  const focus = createModalFocusGuard({
+    isOpen: () => ctx.state.subtitleSelectionModalOpen,
+    getModalRoot: () => dom.modal,
+    getPreferredFocusTargets: () => [dom.primary, dom.secondary, dom.apply],
+    getFallbackFocusTarget: () => dom.close,
+    isModalLayer: ctx.platform.isModalLayer,
+  });
+
+  function status(message: string, error = false): void {
+    dom.status.textContent = message;
+    dom.status.classList.toggle('error', error);
+  }
+
+  function updateControls(): void {
+    const disabled = pending || !snapshot;
+    dom.primary.disabled = disabled;
+    dom.secondary.disabled = disabled;
+    const duplicate = dom.primary.value !== 'no' && dom.primary.value === dom.secondary.value;
+    dom.apply.disabled = disabled || duplicate;
+    for (const option of dom.secondary.options)
+      option.disabled = option.value !== 'no' && option.value === dom.primary.value;
+  }
+
+  function populate(select: HTMLSelectElement, selected: number | null): void {
+    select.replaceChildren();
+    for (const track of [{ id: null, label: 'None' }, ...(snapshot?.tracks ?? [])]) {
+      const option = document.createElement('option');
+      option.value = track.id === null ? 'no' : String(track.id);
+      option.textContent = track.label;
+      select.append(option);
+    }
+    select.value = selected === null ? 'no' : String(selected);
+  }
+
+  async function refresh(openGeneration: number): Promise<void> {
+    try {
+      const next = await window.electronAPI.getSubtitleSelection();
+      if (generation !== openGeneration || !ctx.state.subtitleSelectionModalOpen) return;
+      snapshot = next;
+      populate(dom.primary, next.primary);
+      populate(dom.secondary, next.secondary);
+      status(
+        next.tracks.length
+          ? 'Choose subtitle tracks, then apply.'
+          : 'No subtitle tracks loaded in this video.',
+      );
+    } catch (cause) {
+      if (generation !== openGeneration || !ctx.state.subtitleSelectionModalOpen) return;
+      status(cause instanceof Error ? cause.message : 'Could not read subtitle tracks.', true);
+    } finally {
+      if (generation === openGeneration && ctx.state.subtitleSelectionModalOpen) {
+        pending = false;
+        updateControls();
+        focus.focusFallbackTarget();
+      }
+    }
+  }
+
+  function open(): void {
+    if (ctx.state.subtitleSelectionModalOpen) return;
+    priorFocus = document.activeElement;
+    snapshot = null;
+    pending = true;
+    generation += 1;
+    populate(dom.primary, null);
+    populate(dom.secondary, null);
+    status('Loading subtitle tracks...');
+    updateControls();
+    ctx.state.subtitleSelectionModalOpen = true;
+    options.syncSettingsModalSubtitleSuppression();
+    dom.modal.classList.remove('hidden');
+    dom.modal.setAttribute('aria-hidden', 'false');
+    syncOverlayMouseIgnoreState(ctx);
+    focus.attach();
+    focus.focusFallbackTarget();
+    window.electronAPI.notifyOverlayModalOpened('subtitle-selection');
+    void refresh(generation);
+  }
+
+  function close(): void {
+    if (!ctx.state.subtitleSelectionModalOpen) return;
+    generation += 1;
+    ctx.state.subtitleSelectionModalOpen = false;
+    options.syncSettingsModalSubtitleSuppression();
+    dom.modal.classList.add('hidden');
+    dom.modal.setAttribute('aria-hidden', 'true');
+    focus.detach();
+    window.electronAPI.notifyOverlayModalClosed('subtitle-selection');
+    syncOverlayMouseIgnoreState(ctx);
+    if (priorFocus instanceof HTMLElement) priorFocus.focus({ preventScroll: true });
+    priorFocus = null;
+  }
+
+  async function apply(): Promise<void> {
+    if (dom.apply.disabled || pending || !snapshot) return;
+    const openGeneration = generation;
+    pending = true;
+    updateControls();
+    status('Applying subtitle tracks...');
+    try {
+      await window.electronAPI.applySubtitleSelection({
+        mediaPath: snapshot.mediaPath,
+        primary: dom.primary.value === 'no' ? null : Number(dom.primary.value),
+        secondary: dom.secondary.value === 'no' ? null : Number(dom.secondary.value),
+      });
+      if (generation === openGeneration) close();
+    } catch (cause) {
+      if (generation === openGeneration)
+        status(cause instanceof Error ? cause.message : 'Could not select subtitle tracks.', true);
+    } finally {
+      if (generation === openGeneration) {
+        pending = false;
+        updateControls();
+      }
+    }
+  }
+
+  function handleKeydown(event: KeyboardEvent): boolean {
+    if (event.key === 'Escape') {
+      event.preventDefault();
+      close();
+    } else if (
+      event.key === 'Enter' &&
+      !(event.target instanceof HTMLSelectElement) &&
+      event.target !== dom.close
+    ) {
+      event.preventDefault();
+      void apply();
+    }
+    return true;
+  }
+
+  function wireDomEvents(): void {
+    dom.close.addEventListener('click', close);
+    dom.apply.addEventListener('click', () => void apply());
+    dom.primary.addEventListener('change', () => {
+      if (dom.primary.value !== 'no' && dom.primary.value === dom.secondary.value)
+        dom.secondary.value = 'no';
+      updateControls();
+    });
+    dom.secondary.addEventListener('change', updateControls);
+  }
+
+  return { open, close, handleKeydown, wireDomEvents, dispose: () => focus.detach() };
+}

src/renderer/overlay-mouse-ignore.ts

@@ -10,6 +10,7 @@ function isBlockingOverlayModalOpen(state: RendererState): boolean {
     state.youtubePickerModalOpen ||
     state.kikuModalOpen ||
     state.runtimeOptionsModalOpen ||
+    state.subtitleSelectionModalOpen ||
     state.subsyncModalOpen ||
     state.subtitleGenerationModalOpen ||
     state.sessionHelpModalOpen,

src/renderer/renderer.ts

@@ -44,6 +44,7 @@ import { wireSubtitleSidebarSelection } from './modals/subtitle-sidebar-selectio
 import { isControllerInteractionBlocked } from './controller-interaction-blocking.js';
 import { createCharacterDictionaryModal } from './modals/character-dictionary.js';
 import { createRuntimeOptionsModal } from './modals/runtime-options.js';
+import { createSubtitleSelectionModal } from './modals/subtitle-selection';
 import { createSubsyncModal } from './modals/subsync.js';
 import { createSubtitleGenerationModal } from './modals/subtitle-generation.js';
 import { createYoutubeTrackPickerModal } from './modals/youtube-track-picker.js';
@@ -153,6 +154,12 @@ const modalDescriptors = [
     close: () => characterDictionaryModal.closeCharacterDictionaryModal(),
     suppressesSubtitles: true,
   },
+  {
+    id: 'subtitle-selection',
+    isOpen: () => ctx.state.subtitleSelectionModalOpen,
+    close: () => subtitleSelectionModal.close(),
+    suppressesSubtitles: true,
+  },
   {
     id: 'subsync',
     isOpen: () => ctx.state.subsyncModalOpen,
@@ -216,6 +223,9 @@ const characterDictionaryModal = createCharacterDictionaryModal(ctx, {
   modalStateReader: { isAnyModalOpen },
   syncSettingsModalSubtitleSuppression,
 });
+const subtitleSelectionModal = createSubtitleSelectionModal(ctx, {
+  syncSettingsModalSubtitleSuppression,
+});
 const subsyncModal = createSubsyncModal(ctx, {
   modalStateReader: { isAnyModalOpen },
   syncSettingsModalSubtitleSuppression,
@@ -293,6 +303,7 @@ const mediaTimingReviewModal = createMediaTimingReviewModal(ctx, {
 const keyboardHandlers = createKeyboardHandlers(ctx, {
   handleRuntimeOptionsKeydown: runtimeOptionsModal.handleRuntimeOptionsKeydown,
   handleCharacterDictionaryKeydown: characterDictionaryModal.handleCharacterDictionaryKeydown,
+  handleSubtitleSelectionKeydown: subtitleSelectionModal.handleKeydown,
   handleSubsyncKeydown: subsyncModal.handleSubsyncKeydown,
   handleSubtitleGenerationKeydown: subtitleGenerationModal.handleKeydown,
   handleKikuKeydown: kikuModal.handleKikuKeydown,
@@ -624,6 +635,9 @@ function registerModalOpenHandlers(): void {
       youtubePickerModal.closeYoutubePickerModal();
     });
   });
+  window.electronAPI.onSubtitleSelectionOpen(() => {
+    runGuarded('subtitle-selection:open', () => subtitleSelectionModal.open());
+  });
   window.electronAPI.onSubsyncManualOpen((payload: SubsyncManualPayload) => {
     runGuarded('subsync:manual-open', () => {
       subsyncModal.openSubsyncModal(payload);
@@ -849,6 +863,7 @@ async function init(): Promise<void> {
   playlistBrowserModal.wireDomEvents();
   kikuModal.wireDomEvents();
   runtimeOptionsModal.wireDomEvents();
+  subtitleSelectionModal.wireDomEvents();
   subsyncModal.wireDomEvents();
   subtitleGenerationModal.wireDomEvents();
   controllerSelectModal.wireDomEvents();
@@ -858,6 +873,7 @@ async function init(): Promise<void> {
   subtitleSidebarModal.wireDomEvents();
   characterDictionaryModal.wireDomEvents();
   window.addEventListener('beforeunload', () => {
+    subtitleSelectionModal.dispose();
     subtitleGenerationModal.dispose();
     subtitleSidebarModal.disposeDomEvents();
   });
@@ -867,9 +883,13 @@ async function init(): Promise<void> {
       runtimeOptionsModal.updateRuntimeOptions(options);
     });
   });
+  window.electronAPI.onSessionBindingsChanged(keyboardHandlers.updateSessionBindings);
   window.electronAPI.onConfigHotReload((payload: ConfigHotReloadPayload) => {
     runGuarded('config:hot-reload', () => {
-      keyboardHandlers.updateSessionBindings(payload.sessionBindings);
+      void window.electronAPI
+        .getSessionBindings()
+        .then(keyboardHandlers.updateSessionBindings)
+        .catch((error: unknown) => console.error('Could not refresh session bindings', error));
       void keyboardHandlers.refreshConfiguredShortcuts();
       subtitleRenderer.applySubtitleStyle(payload.subtitleStyle);
       subtitleRenderer.updatePrimarySubMode(payload.primarySubMode);

src/renderer/state.ts

@@ -89,6 +89,7 @@ export type RendererState = {
   characterDictionaryStatus: string;
 
   subsyncModalOpen: boolean;
+  subtitleSelectionModalOpen: boolean;
   subtitleGenerationModalOpen: boolean;
   subsyncSubtitleTracks: SubsyncSubtitleTrack[];
   subsyncSubmitting: boolean;
@@ -223,6 +224,7 @@ export function createRendererState(): RendererState {
     characterDictionaryStatus: '',
 
     subsyncModalOpen: false,
+    subtitleSelectionModalOpen: false,
     subtitleGenerationModalOpen: false,
     subsyncSubtitleTracks: [],
     subsyncSubmitting: false,

src/renderer/style.css

@@ -3228,6 +3228,16 @@ iframe[id^='yomitan-popup'],
   padding: 8px 10px;
 }
 
+.subsync-field select:focus-visible {
+  outline: 2px solid var(--ctp-blue);
+  outline-offset: 2px;
+}
+
+#subtitleSelectionModal .kiku-confirm-button:disabled {
+  opacity: 0.5;
+  cursor: default;
+}
+
 .subsync-footer {
   display: flex;
   justify-content: flex-end;

src/shared/ipc/contracts.ts

@@ -4,6 +4,7 @@ import type { RuntimeOptionId, RuntimeOptionValue } from '../../types/runtime-op
 export const OVERLAY_HOSTED_MODALS = [
   'runtime-options',
   'subsync',
+  'subtitle-selection',
   'subtitle-generation',
   'jimaku',
   'tsukihime',
@@ -51,6 +52,8 @@ export const IPC_CHANNELS = {
     dispatchSessionAction: 'session-action:dispatch',
   },
   request: {
+    getSubtitleSelection: 'subtitle-selection:get',
+    applySubtitleSelection: 'subtitle-selection:apply',
     requestSubtitleGenerationOpen: 'subtitle-generation:open',
     getSubtitleGenerationStatus: 'subtitle-generation:status',
     startSubtitleGeneration: 'subtitle-generation:start',
@@ -143,6 +146,7 @@ export const IPC_CHANNELS = {
     mediaTimingReviewResolve: 'media-timing-review:resolve',
   },
   event: {
+    subtitleSelectionOpen: 'subtitle-selection:opened',
     subtitleGenerationOpen: 'subtitle-generation:opened',
     subtitleGenerationProgress: 'subtitle-generation:progress',
     subtitleSet: 'subtitle:set',
@@ -174,6 +178,7 @@ export const IPC_CHANNELS = {
     controllerDebugOpen: 'controller-debug:open',
     subtitleSidebarToggle: 'subtitle-sidebar:toggle',
     primarySubtitleBarToggle: 'primary-subtitle-bar:toggle',
+    sessionBindingsChanged: 'session-bindings:changed',
     configHotReload: 'config:hot-reload',
     overlayNotification: 'overlay:notification',
     notificationHistoryToggle: 'notification-history:toggle',

src/shared/ipc/validators.ts

@@ -44,6 +44,7 @@ const SESSION_ACTION_IDS: SessionActionId[] = [
   'openControllerDebug',
   'openJimaku',
   'openTsukihime',
+  'openSubtitleSelection',
   'openSubtitleGeneration',
   'openYoutubePicker',
   'openPlaylistBrowser',

src/shared/mpv-input-bindings.test.ts

@@ -103,3 +103,13 @@ test('SubMiner ownership recognizes leading mpv prefixes without matching comman
     ['d', 'e', 'f', 'g'],
   );
 });
+
+test('sequence conflict discovery allows winning ignore bindings used by mpv sequence prefixes', () => {
+  const bindings = [
+    { key: 'g', cmd: 'show-text old', priority: 0 },
+    { key: 'g', cmd: 'no-osd ignore', priority: 1 },
+    { key: 'h', cmd: 'show-text action', priority: 0 },
+  ];
+  assert.deepEqual(parseMpvInputBindingKeys(bindings), ['g', 'h']);
+  assert.deepEqual(parseMpvInputBindingKeys(bindings, { includeIgnored: false }), ['h']);
+});

src/shared/mpv-input-bindings.ts

@@ -59,9 +59,12 @@ export function keyboardEventToMpvKey(
   return normalizeMpvInputKey([...modifiers, key].join('+'));
 }
 
-export function parseMpvInputBindingKeys(value: unknown): string[] {
+export function parseMpvInputBindingKeys(
+  value: unknown,
+  { includeIgnored = true }: { includeIgnored?: boolean } = {},
+): string[] {
   if (!Array.isArray(value)) return [];
-  const bindings = new Map<string, { priority: number; owned: boolean }>();
+  const bindings = new Map<string, { priority: number; owned: boolean; ignored: boolean }>();
   for (const candidate of value) {
     const entry: unknown = candidate;
     if (
@@ -94,8 +97,14 @@ export function parseMpvInputBindingKeys(value: unknown): string[] {
       entry.priority > previous.priority ||
       (entry.priority === previous.priority && owned)
     ) {
-      bindings.set(key, { priority: entry.priority, owned });
+      bindings.set(key, {
+        priority: entry.priority,
+        owned,
+        ignored: entry.cmd.trim().replace(MPV_COMMAND_PREFIXES, '') === 'ignore',
+      });
     }
   }
-  return [...bindings].filter(([, binding]) => !binding.owned).map(([key]) => key);
+  return [...bindings]
+    .filter(([, binding]) => !binding.owned && (includeIgnored || !binding.ignored))
+    .map(([key]) => key);
 }

src/shared/session-key-sequences.ts

@@ -0,0 +1,71 @@
+import type {
+  CompiledSessionBinding,
+  SessionBindingWarning,
+  SessionKeySpec,
+} from '../types/session-bindings';
+
+export interface SessionKeyReservation {
+  key: SessionKeySpec;
+  path: string;
+}
+
+export function getSessionSequencePrefix(key: SessionKeySpec): SessionKeySpec | null {
+  const match = /^(Key[A-Z])-Key[A-Z]$/.exec(key.code);
+  return match?.[1] ? { code: match[1], modifiers: key.modifiers } : null;
+}
+
+function signature(key: SessionKeySpec): string {
+  return [...key.modifiers, key.code].join('+');
+}
+
+export function resolveSessionSequenceConflicts(
+  bindings: CompiledSessionBinding[],
+  reservations: SessionKeyReservation[] = [],
+): { bindings: CompiledSessionBinding[]; warnings: SessionBindingWarning[] } {
+  const singles = new Map<string, string[]>();
+  for (const { key, path } of [
+    ...bindings.map((binding) => ({ key: binding.key, path: binding.sourcePath })),
+    ...reservations,
+  ]) {
+    if (getSessionSequencePrefix(key)) continue;
+    const id = signature(key);
+    singles.set(id, [...(singles.get(id) ?? []), path]);
+  }
+  const warnings: SessionBindingWarning[] = [];
+  const effective = bindings.filter((binding) => {
+    const prefix = getSessionSequencePrefix(binding.key);
+    if (!prefix) return true;
+    const conflicts = singles.get(signature(prefix));
+    if (!conflicts?.length) return true;
+    const paths = [...new Set(conflicts)];
+    warnings.push({
+      kind: 'conflict',
+      path: binding.sourcePath,
+      value: binding.originalKey,
+      conflictingPaths: paths,
+      message: `Disabled sequence "${binding.originalKey}" (${binding.sourcePath}): its first key is reserved by ${paths.join(', ')}. Single-key bindings take priority; remap the sequence or its conflicting binding.`,
+    });
+    return false;
+  });
+  return { bindings: effective, warnings };
+}
+
+// Imported mpv keys preserve case: g and G are different strokes.
+export function reserveMpvSequencePrefixes(keys: string[]): SessionKeyReservation[] {
+  return keys.flatMap((value) => {
+    const parts = value.split('+');
+    const letter = parts.pop();
+    if (!letter || !/^[a-z]$/i.test(letter)) return [];
+    const modifiers: SessionKeySpec['modifiers'] = [];
+    if (parts.includes('ctrl')) modifiers.push('ctrl');
+    if (parts.includes('alt')) modifiers.push('alt');
+    if (parts.includes('shift') || /^[A-Z]$/.test(letter)) modifiers.push('shift');
+    if (parts.includes('meta')) modifiers.push('meta');
+    return [
+      {
+        key: { code: `Key${letter.toUpperCase()}`, modifiers },
+        path: `mpv input binding "${value}"`,
+      },
+    ];
+  });
+}

src/shared/subtitle-selection.ts

@@ -0,0 +1,33 @@
+export interface SubtitleSelectionState {
+  mediaPath: string;
+  tracks: { id: number; label: string }[];
+  primary: number | null;
+  secondary: number | null;
+}
+
+export type SubtitleSelectionRequest = Pick<
+  SubtitleSelectionState,
+  'mediaPath' | 'primary' | 'secondary'
+>;
+
+export function parseSubtitleSelectionRequest(value: unknown): SubtitleSelectionRequest {
+  if (
+    typeof value !== 'object' ||
+    value === null ||
+    !('mediaPath' in value) ||
+    typeof value.mediaPath !== 'string' ||
+    !value.mediaPath ||
+    !('primary' in value) ||
+    !isTrackSelection(value.primary) ||
+    !('secondary' in value) ||
+    !isTrackSelection(value.secondary)
+  )
+    throw new Error('Invalid subtitle selection.');
+  if (value.primary !== null && value.primary === value.secondary)
+    throw new Error('Choose different primary and secondary tracks.');
+  return { mediaPath: value.mediaPath, primary: value.primary, secondary: value.secondary };
+}
+
+function isTrackSelection(value: unknown): value is number | null {
+  return value === null || (typeof value === 'number' && Number.isSafeInteger(value) && value > 0);
+}

src/types/config.ts

@@ -126,6 +126,7 @@ export interface ShortcutsConfig {
   openRuntimeOptions?: string | null;
   openJimaku?: string | null;
   openTsukihime?: string | null;
+  openSubtitleSelection?: string | null;
   openSubtitleGeneration?: string | null;
   openSessionHelp?: string | null;
   openControllerSelect?: string | null;
@@ -152,6 +153,7 @@ export interface Config {
   shortcuts?: RawShortcutsConfig;
   secondarySub?: SecondarySubConfig;
   subsync?: SubsyncConfig;
+  subtitleSelection?: { enabled?: boolean };
   subtitleGeneration?: Partial<SubtitleGenerationConfig>;
   startupWarmups?: StartupWarmupsConfig;
   subtitleStyle?: SubtitleStyleConfig;
@@ -304,6 +306,7 @@ export interface ResolvedConfig {
   shortcuts: Required<ShortcutsConfig>;
   secondarySub: Required<SecondarySubConfig>;
   subsync: Required<SubsyncConfig>;
+  subtitleSelection: { enabled: boolean };
   subtitleGeneration: SubtitleGenerationConfig;
   startupWarmups: {
     lowPowerMode: boolean;

src/types/runtime.ts

@@ -525,6 +525,13 @@ export interface ElectronAPI {
   focusMainWindow: () => Promise<void>;
   activatePlaybackWindowForOverlayInteraction: () => Promise<boolean>;
   getSubtitleStyle: () => Promise<SubtitleRendererStyleConfig | null>;
+  onSubtitleSelectionOpen: (callback: () => void) => void;
+  getSubtitleSelection: () => Promise<
+    import('../shared/subtitle-selection').SubtitleSelectionState
+  >;
+  applySubtitleSelection: (
+    request: import('../shared/subtitle-selection').SubtitleSelectionRequest,
+  ) => Promise<void>;
   onSubsyncManualOpen: (callback: (payload: SubsyncManualPayload) => void) => void;
   runSubsyncManual: (request: SubsyncManualRunRequest) => Promise<SubsyncResult>;
   onKikuFieldGroupingRequest: (callback: (data: KikuFieldGroupingRequestData) => void) => void;
@@ -604,6 +611,7 @@ export interface ElectronAPI {
     modal:
       | 'runtime-options'
       | 'subsync'
+      | 'subtitle-selection'
       | 'subtitle-generation'
       | 'jimaku'
       | 'tsukihime'
@@ -622,6 +630,7 @@ export interface ElectronAPI {
     modal:
       | 'runtime-options'
       | 'subsync'
+      | 'subtitle-selection'
       | 'subtitle-generation'
       | 'jimaku'
       | 'tsukihime'
@@ -637,6 +646,7 @@ export interface ElectronAPI {
       | 'changelog',
   ) => void;
   reportOverlayContentBounds: (measurement: OverlayContentMeasurement) => void;
+  onSessionBindingsChanged: (callback: (bindings: CompiledSessionBinding[]) => void) => void;
   onConfigHotReload: (callback: (payload: ConfigHotReloadPayload) => void) => void;
 }
 

src/types/session-bindings.ts

@@ -23,6 +23,7 @@ export type SessionActionId =
   | 'openControllerDebug'
   | 'openJimaku'
   | 'openTsukihime'
+  | 'openSubtitleSelection'
   | 'openSubtitleGeneration'
   | 'openYoutubePicker'
   | 'openPlaylistBrowser'