diff --git a/docs/subagents/agents/codex-task85-20260219T233711Z-46hc.md b/docs/subagents/agents/codex-task85-20260219T233711Z-46hc.md
index 3193688..338a5ef 100644
--- a/docs/subagents/agents/codex-task85-20260219T233711Z-46hc.md
+++ b/docs/subagents/agents/codex-task85-20260219T233711Z-46hc.md
@@ -411,3 +411,6 @@
 - [2026-02-20T09:32:11Z] test: `bun run build` pass (expected macOS helper Swift cache fallback) + targeted suites pass: `cli-command-context-main-deps`, `mpv-main-event-main-deps`, `mpv-main-event-bindings`, `mpv-client-runtime-service-main-deps`, `subtitle-tokenization-main-deps`.
 - [2026-02-20T09:33:19Z] progress: completed another 5-block safe normalization in `main.ts` for lifecycle/startup wiring: prebuilt deps handlers for `onWillQuitCleanup`, `shouldRestoreWindowsOnActivate`, `restoreWindowsOnActivate`, `reloadConfig`, and `criticalConfigError`.
 - [2026-02-20T09:33:19Z] test: `bun run build` pass (expected macOS helper Swift cache fallback) + targeted suites pass for `app-lifecycle-main-cleanup`, `app-lifecycle-main-activate`, `startup-config-main-deps`, and `startup-config`.
+- [2026-02-20T09:35:02Z] progress: extracted protocol URL registration dependency assembly to `protocol-url-handlers-main-deps.ts` and rewired main protocol registration call through builder.
+- [2026-02-20T09:35:02Z] progress: normalized `cycleSecondarySubMode` to use prebuilt deps builder constant (avoids per-call rebuild).
+- [2026-02-20T09:35:02Z] test: `bun run build` pass (expected macOS helper Swift cache fallback) + `protocol-url-handlers*` and `secondary-sub-mode-main-deps` tests pass.
diff --git a/src/main.ts b/src/main.ts
index 7281262..026d7c2 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -195,6 +195,7 @@ import {
   createBuildSaveSubtitlePositionMainDepsHandler,
 } from './main/runtime/subtitle-position-main-deps';
 import { registerProtocolUrlHandlers } from './main/runtime/protocol-url-handlers';
+import { createBuildRegisterProtocolUrlHandlersMainDepsHandler } from './main/runtime/protocol-url-handlers-main-deps';
 import { createHandleJellyfinAuthCommands } from './main/runtime/jellyfin-cli-auth';
 import { createRunJellyfinCommandHandler } from './main/runtime/jellyfin-command-dispatch';
 import { createBuildRunJellyfinCommandMainDepsHandler } from './main/runtime/jellyfin-command-dispatch-main-deps';
@@ -1892,7 +1893,8 @@ const saveSubtitlePosition = createSaveSubtitlePositionHandler(
 
 registerSubminerProtocolClient();
 
-registerProtocolUrlHandlers({
+const buildRegisterProtocolUrlHandlersMainDepsHandler =
+  createBuildRegisterProtocolUrlHandlersMainDepsHandler({
   registerOpenUrl: (listener) => {
     app.on('open-url', listener);
   },
@@ -1908,6 +1910,7 @@ registerProtocolUrlHandlers({
     logger.warn('Unhandled second-instance protocol URL', { rawUrl });
   },
 });
+registerProtocolUrlHandlers(buildRegisterProtocolUrlHandlersMainDepsHandler());
 
 const buildOnWillQuitCleanupDepsHandler = createBuildOnWillQuitCleanupDepsHandler({
     destroyTray: () => destroyTray(),
@@ -2511,23 +2514,25 @@ function getConfiguredShortcuts() {
   return getConfiguredShortcutsHandler();
 }
 
+const buildCycleSecondarySubModeMainDepsHandler = createBuildCycleSecondarySubModeMainDepsHandler(
+  {
+    getSecondarySubMode: () => appState.secondarySubMode,
+    setSecondarySubMode: (mode: SecondarySubMode) => {
+      appState.secondarySubMode = mode;
+    },
+    getLastSecondarySubToggleAtMs: () => appState.lastSecondarySubToggleAtMs,
+    setLastSecondarySubToggleAtMs: (timestampMs: number) => {
+      appState.lastSecondarySubToggleAtMs = timestampMs;
+    },
+    broadcastToOverlayWindows: (channel, mode) => {
+      broadcastToOverlayWindows(channel, mode);
+    },
+    showMpvOsd: (text: string) => showMpvOsd(text),
+  },
+);
+
 function cycleSecondarySubMode(): void {
-  cycleSecondarySubModeCore(
-    createBuildCycleSecondarySubModeMainDepsHandler({
-      getSecondarySubMode: () => appState.secondarySubMode,
-      setSecondarySubMode: (mode: SecondarySubMode) => {
-        appState.secondarySubMode = mode;
-      },
-      getLastSecondarySubToggleAtMs: () => appState.lastSecondarySubToggleAtMs,
-      setLastSecondarySubToggleAtMs: (timestampMs: number) => {
-        appState.lastSecondarySubToggleAtMs = timestampMs;
-      },
-      broadcastToOverlayWindows: (channel, mode) => {
-        broadcastToOverlayWindows(channel, mode);
-      },
-      showMpvOsd: (text: string) => showMpvOsd(text),
-    })(),
-  );
+  cycleSecondarySubModeCore(buildCycleSecondarySubModeMainDepsHandler());
 }
 
 const buildAppendToMpvLogMainDepsHandler = createBuildAppendToMpvLogMainDepsHandler({
diff --git a/src/main/runtime/protocol-url-handlers-main-deps.test.ts b/src/main/runtime/protocol-url-handlers-main-deps.test.ts
new file mode 100644
index 0000000..5a6087a
--- /dev/null
+++ b/src/main/runtime/protocol-url-handlers-main-deps.test.ts
@@ -0,0 +1,29 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+import { createBuildRegisterProtocolUrlHandlersMainDepsHandler } from './protocol-url-handlers-main-deps';
+
+test('protocol url handlers main deps builder maps callbacks', () => {
+  const calls: string[] = [];
+  const deps = createBuildRegisterProtocolUrlHandlersMainDepsHandler({
+    registerOpenUrl: () => calls.push('open-register'),
+    registerSecondInstance: () => calls.push('second-register'),
+    handleAnilistSetupProtocolUrl: () => true,
+    findAnilistSetupDeepLinkArgvUrl: () => 'subminer://anilist-setup',
+    logUnhandledOpenUrl: (rawUrl) => calls.push(`open:${rawUrl}`),
+    logUnhandledSecondInstanceUrl: (rawUrl) => calls.push(`second:${rawUrl}`),
+  })();
+
+  deps.registerOpenUrl(() => {});
+  deps.registerSecondInstance(() => {});
+  assert.equal(deps.handleAnilistSetupProtocolUrl('subminer://anilist-setup'), true);
+  assert.equal(deps.findAnilistSetupDeepLinkArgvUrl(['x']), 'subminer://anilist-setup');
+  deps.logUnhandledOpenUrl('subminer://noop');
+  deps.logUnhandledSecondInstanceUrl('subminer://noop');
+
+  assert.deepEqual(calls, [
+    'open-register',
+    'second-register',
+    'open:subminer://noop',
+    'second:subminer://noop',
+  ]);
+});
diff --git a/src/main/runtime/protocol-url-handlers-main-deps.ts b/src/main/runtime/protocol-url-handlers-main-deps.ts
new file mode 100644
index 0000000..a2a0554
--- /dev/null
+++ b/src/main/runtime/protocol-url-handlers-main-deps.ts
@@ -0,0 +1,16 @@
+import type { registerProtocolUrlHandlers } from './protocol-url-handlers';
+
+type RegisterProtocolUrlHandlersMainDeps = Parameters<typeof registerProtocolUrlHandlers>[0];
+
+export function createBuildRegisterProtocolUrlHandlersMainDepsHandler(
+  deps: RegisterProtocolUrlHandlersMainDeps,
+) {
+  return (): RegisterProtocolUrlHandlersMainDeps => ({
+    registerOpenUrl: (listener) => deps.registerOpenUrl(listener),
+    registerSecondInstance: (listener) => deps.registerSecondInstance(listener),
+    handleAnilistSetupProtocolUrl: (rawUrl: string) => deps.handleAnilistSetupProtocolUrl(rawUrl),
+    findAnilistSetupDeepLinkArgvUrl: (argv: string[]) => deps.findAnilistSetupDeepLinkArgvUrl(argv),
+    logUnhandledOpenUrl: (rawUrl: string) => deps.logUnhandledOpenUrl(rawUrl),
+    logUnhandledSecondInstanceUrl: (rawUrl: string) => deps.logUnhandledSecondInstanceUrl(rawUrl),
+  });
+}