diff --git a/runtime/include/window_fullscreen.h b/runtime/include/window_fullscreen.h
index 2a74dd5c..741187c7 100644
--- a/runtime/include/window_fullscreen.h
+++ b/runtime/include/window_fullscreen.h
@@ -65,7 +65,13 @@ static inline int psx_window_fullscreen_set(SDL_Window* window,
         SDL_SetWindowBordered(window, SDL_FALSE);
         SDL_SetWindowResizable(window, SDL_FALSE);
         SDL_SetWindowPosition(window, desktop.x, desktop.y);
-        SDL_SetWindowSize(window, desktop.w, desktop.h);
+        /* One row taller than the display: a window exactly covering it is
+         * promoted by Windows to a direct/independent flip, and OpenGL swaps
+         * from the render thread then stop reaching the screen (NVIDIA: the
+         * image freezes while the game runs; any overlay -- taskbar, another
+         * window -- forces composition and the frames reappear). The extra
+         * row is off-screen; the window stays composed. */
+        SDL_SetWindowSize(window, desktop.w, desktop.h + 1);
         SDL_SyncWindow(window);
 #elif defined(PSX_SDL3)
         if (!SDL_SetWindowFullscreen(window, true)) return -1;
diff --git a/runtime/tests/test_window_fullscreen.cpp b/runtime/tests/test_window_fullscreen.cpp
index a8229c5b..21af1d42 100644
--- a/runtime/tests/test_window_fullscreen.cpp
+++ b/runtime/tests/test_window_fullscreen.cpp
@@ -35,7 +35,8 @@ int main() {
         SDL_Rect bounds{};
         SDL_GetDisplayBounds(SDL_GetDisplayForWindow(window), &bounds);
         int full_w, full_h; SDL_GetWindowSize(window, &full_w, &full_h);
-        check(full_w == bounds.w && full_h == bounds.h, "borderless covers the current display");
+        check(full_w == bounds.w && full_h == bounds.h + 1,
+              "borderless covers the current display (one row over: stays composed)");
         check(!SDL_CursorVisible(), "fullscreen cursor hidden");
         SDL_DisplayMode current{};
         check(SDL_GetCurrentDisplayMode(original_display, &current) == 0 &&