Fix trampoline crash by replacing MenuCursor hooks

The previous MenuCursor detour hooks crashed at startup with 'REL/Trampoline.cpp: Failed to handle allocation request' because the plugin never allocated F4SE trampoline memory. Replaced detours with a MainMenu::AdvanceMovie vtable hook (which requires no trampoline) that re-expands cursor bounds immediately after vanilla title-screen parallax runs. Added UIAdvanceMenusFunctionCompleteEvent sink as additional safety net. Changed main menu disableFocusMenu to true to avoid fighting vanilla cursor/parallax state.

changelog.md

@@ -28,7 +28,8 @@ For testing notes, milestone summaries, known issues, and next steps, see [`docs
 - `main-menu/script.js` now includes `window.CO_App` object with `setPointerMode()` for C++ to invoke, and `handleControllerInput()` stub for gamepad dispatch (wired in v1.1 when dispatch is complete).
 
 ### Fixed
-- Mouse cursor could not move away from the center of the screen while the custom main menu overlay was shown. Root causes: (1) overlay could appear during Please Stand By / intro Binks; (2) vanilla `RE::MenuCursor` min/max bounds were never cleared. Fixed by gating show on intro completion (`PlayBinkMenu` closed, main panel/list visible, `userEngaged`, or short fallback) plus strict `MAIN_STATE` when GFx publishes it; and clearing `MenuCursor` constraints to full window size each frame while the custom menu owns input.
+- Game crashed on load with `REL/Trampoline.cpp: Failed to handle allocation request` because `MenuCursor` detour hooks required trampoline memory the plugin never allocated. Replaced detours with a `MainMenu::AdvanceMovie` vtable hook (no trampoline) that re-expands cursor bounds after vanilla parallax runs.
+- Mouse cursor could not move away from the center of the screen while the custom main menu overlay was shown. Root causes: (1) overlay could appear during Please Stand By / intro Binks; (2) vanilla `RE::MenuCursor` min/max bounds were re-applied each frame by title-screen parallax. Fixed by gating show on intro completion, clearing constraints each frame, releasing again after `MainMenu::AdvanceMovie` and on `UIAdvanceMenusFunctionCompleteEvent`, and using `disableFocusMenu=true` for the main menu overlay.
 
 ### Changed
 - Pause menu settings panel fades and slides in subtly on open and animates out on back (opacity + 10px vertical offset, 220ms ease-out).

docs/dev-log.md

@@ -7,6 +7,58 @@ failed experiments, successful tests, and next steps.
 
 ---
 
+---
+
+## 2026-07-07 - Fix: Trampoline Crash on Load (MenuCursor Hook Replaced)
+
+### Summary
+The previous `MenuCursor::SetCursorConstraintsRaw` / `CenterCursor` detour hooks crashed at startup with `REL/Trampoline.cpp: Failed to handle allocation request` (Allocate Size: 14, Free Size: 0) because the plugin never allocated F4SE trampoline memory. Removed the detours and instead hook `MainMenu::AdvanceMovie` via vtable (same pattern as existing MainMenu input hooks) to re-expand cursor bounds immediately after vanilla title-screen parallax runs. Kept the `UIAdvanceMenusFunctionCompleteEvent` sink and per-frame `ReleaseMenuCursorConstraints()` as additional safety.
+
+### Files Changed
+- `plugin/src/F4TPrismaUI.cpp`
+- `changelog.md`
+- `docs/dev-log.md`
+
+### Testing
+- Built via `xmake build`.
+- Launch game: should no longer show trampoline error dialog; custom main menu should appear after intro.
+- Verify mouse reaches all screen edges on title screen.
+
+### Known Issues
+- Cursor snap-back fix needs in-game re-verification with the vtable-hook approach.
+
+### Next Steps
+- User verification after deploy.
+
+## 2026-07-06 - Fix: Main Menu Cursor Snap-Back (MenuCursor Hooks)
+
+### Summary
+The custom main menu overlay still trapped the mouse in a central box even after per-frame `ReleaseMenuCursorConstraints()`. Vanilla `MainMenu` title-screen parallax calls `MenuCursor::SetCursorConstraintsRaw` and `CenterCursor` every frame **after** our task cleared bounds, immediately re-tightening them. Fixed by hooking both functions to expand constraints to the full window and skip re-centering while a custom overlay is visible, registering a `UIAdvanceMenusFunctionCompleteEvent` sink as a post-menu safety net, and using `disableFocusMenu=true` for the main menu (vanilla `MainMenu` already owns a working cursor).
+
+### Files Changed
+- `plugin/src/F4TPrismaUI.cpp`
+- `ui/views/CommonwealthOnline/main-menu/shell.html` (removed stray viewport meta)
+- `changelog.md`
+- `docs/dev-log.md`
+
+### Details
+- `SetCursorConstraintsRaw` hook redirects to `(0, 0, windowWidth, windowHeight)` when main menu or server browser overlay is active.
+- `CenterCursor` hook becomes a no-op while overlays are active.
+- `ReleaseMenuCursorConstraints()` now also calls `SetCursorConstraintsRaw` with full-window dimensions.
+- Main menu `Focus()` now passes `disableFocusMenu=true` so PrismaUI does not open its own FocusMenu on top of vanilla title-screen cursor handling.
+
+### Testing
+- Build via `build-all.bat`.
+- Launch to title screen; wait for custom main menu overlay.
+- Move mouse to all four corners — cursor should not snap back to center.
+- Click each menu row; open MULTIPLAYER and confirm server browser cursor also spans full window.
+
+### Known Issues
+- None currently known for this fix.
+
+### Next Steps
+- User in-game verification.
+
 ## 2026-07-06 - Fix: MenuCursor Constraints + Bink Gating (cursor jolt + early overlay)
 
 ### Summary

plugin/src/F4TPrismaUI.cpp

@@ -50,6 +50,12 @@ namespace F4T::PrismaUI
 		bool g_hasLastCursorPos = false;
 		POINT g_lastCursorPos{};
 
+		using MainMenuAdvanceMovieFn = void(RE::IMenu*, float, std::uint64_t);
+
+		std::uintptr_t g_originalMainMenuAdvanceMovie = 0;
+		bool g_mainMenuAdvanceHookInstalled = false;
+		bool g_menuAdvanceSinkRegistered = false;
+
 		// Forward declarations (definitions appear later in this anonymous namespace;
 		// several functions call each other out of definition order).
 		void HideMainMenuInternal();
@@ -60,6 +66,46 @@ namespace F4T::PrismaUI
 		void CreateServerBrowserView();
 		void SyncBrowserHover();
 		void WatchMainMenuState();
+		void InstallMainMenuCursorReleaseHook();
+		void RegisterMenuAdvanceSink();
+		void ReleaseMenuCursorConstraints();
+
+		[[nodiscard]] bool ShouldOverrideMenuCursorConstraints()
+		{
+			return g_mainMenuVisible || g_browserVisible;
+		}
+
+		void MainMenuAdvanceMovieHook(RE::IMenu* a_this, float a_timeDelta, std::uint64_t a_time)
+		{
+			if (g_originalMainMenuAdvanceMovie != 0) {
+				reinterpret_cast<MainMenuAdvanceMovieFn*>(g_originalMainMenuAdvanceMovie)(a_this, a_timeDelta, a_time);
+			}
+
+			// MainMenu parallax updates MenuCursor bounds during AdvanceMovie; re-expand after vanilla runs.
+			if (ShouldOverrideMenuCursorConstraints()) {
+				ReleaseMenuCursorConstraints();
+			}
+		}
+
+		class MenuAdvanceSink :
+			public RE::BSTEventSink<RE::UIAdvanceMenusFunctionCompleteEvent>
+		{
+		public:
+			RE::BSEventNotifyControl ProcessEvent(
+				const RE::UIAdvanceMenusFunctionCompleteEvent&,
+				RE::BSTEventSource<RE::UIAdvanceMenusFunctionCompleteEvent>* a_source) override
+			{
+				(void)a_source;
+
+				if (ShouldOverrideMenuCursorConstraints()) {
+					ReleaseMenuCursorConstraints();
+				}
+
+				return RE::BSEventNotifyControl::kContinue;
+			}
+		};
+
+		MenuAdvanceSink g_menuAdvanceSink;
 
 		std::string GetLogPrefix()
 		{
@@ -78,6 +124,35 @@ namespace F4T::PrismaUI
 			REX::WARN(std::string_view{ message });
 		}
 
+		void InstallMainMenuCursorReleaseHook()
+		{
+			if (g_mainMenuAdvanceHookInstalled) {
+				return;
+			}
+
+			REL::Relocation<std::uintptr_t> vtable{ RE::MainMenu::VTABLE[0] };
+			g_originalMainMenuAdvanceMovie = vtable.write_vfunc(0x04, &MainMenuAdvanceMovieHook);
+			if (g_originalMainMenuAdvanceMovie != 0) {
+				g_mainMenuAdvanceHookInstalled = true;
+				LogInfo("Installed MainMenu AdvanceMovie hook for MenuCursor release.");
+			} else {
+				LogWarning("MainMenu AdvanceMovie hook failed to install.");
+			}
+		}
+
+		void RegisterMenuAdvanceSink()
+		{
+			if (g_menuAdvanceSinkRegistered) {
+				return;
+			}
+
+			if (auto* source = RE::UIAdvanceMenusFunctionCompleteEvent::GetEventSource()) {
+				source->RegisterSink(&g_menuAdvanceSink);
+				g_menuAdvanceSinkRegistered = true;
+				LogInfo("Registered UIAdvanceMenusFunctionCompleteEvent sink for MenuCursor release.");
+			}
+		}
+
 		void SuppressNativeGameCursor()
 		{
 			auto* ui = RE::UI::GetSingleton();
@@ -116,12 +191,15 @@ namespace F4T::PrismaUI
 				return;
 			}
 
-			// MainMenu keeps a tight MenuCursor box for title-screen parallax; clear it every frame
+			// MainMenu keeps a tight MenuCursor box for title-screen parallax; expand to the full
-			// while our overlay owns input so the OS pointer can reach the full window.
+			// window while our overlay owns input so the OS pointer can reach every edge.
+			menuCursor->SetCursorConstraintsRaw(0, 0, static_cast<std::uint32_t>(width), static_cast<std::uint32_t>(height));
 			menuCursor->minCursorX = 0;
 			menuCursor->minCursorY = 0;
 			menuCursor->maxCursorX = width;
 			menuCursor->maxCursorY = height;
+
+			::ClipCursor(nullptr);
 		}
 
 	void ApplyBrowserPointerMode(bool a_mouseCursorVisible)
@@ -136,12 +214,9 @@ namespace F4T::PrismaUI
 		if (g_mainMenuVisible && g_api && g_api->IsValid(g_mainMenuView)) {
 			activeView = g_mainMenuView;
 			namespace_obj = "window.CO_App";
-			// The main menu is the primary/standalone title-screen UI, not a panel opened
+			// MainMenu is already open with a working title-screen cursor. Keep PrismaUI's
-			// on top of another menu's cursor. Let PrismaUI open its own FocusMenu (kUsesCursor /
+			// FocusMenu overlay suppressed so we do not fight vanilla cursor/parallax state.
-			// kCursor input context) instead of relying on vanilla MainMenu's cursor handling,
+			disableFocusMenu = true;
-			// which re-centers the OS cursor each frame for its background camera parallax and
-			// otherwise pins the pointer to the middle of the screen.
-			disableFocusMenu = false;
 		} else if (g_browserVisible && g_api && g_api->IsValid(g_serverBrowserView)) {
 			activeView = g_serverBrowserView;
 			namespace_obj = "window.CO_App";
@@ -674,6 +749,8 @@ namespace F4T::PrismaUI
 	void OnGameDataReady()
 	{
 		F4T::MainMenuInject::Install();
+		InstallMainMenuCursorReleaseHook();
+		RegisterMenuAdvanceSink();
 
 		g_api = PRISMA_UI_API::RequestPluginAPI<PRISMA_UI_API::IVPrismaUI4>();
 		if (!g_api) {

ui/views/CommonwealthOnline/main-menu/shell.html

@@ -2,7 +2,6 @@
 <html lang="en">
 <head>
   <meta charset="UTF-8">
-  <meta name="viewport" content="width=device-width, initial-scale=1.0">
   <title>Commonwealth Online — Main Menu Shell</title>
   <link rel="stylesheet" href="styles.css">
   <style>