diff --git a/ISLE/isleapp.cpp b/ISLE/isleapp.cpp
index 2e2066d8..6cb0375c 100644
--- a/ISLE/isleapp.cpp
+++ b/ISLE/isleapp.cpp
@@ -447,7 +447,7 @@ SDL_AppResult SDL_AppEvent(void* appstate, SDL_Event* event)
 
 		SDL_Keycode keyCode = event->key.key;
 
-		if (event->key.mod == SDL_KMOD_LALT && keyCode == SDLK_RETURN) {
+		if ((event->key.mod & SDL_KMOD_LALT) && keyCode == SDLK_RETURN) {
 			SDL_SetWindowFullscreen(window, !(SDL_GetWindowFlags(window) & SDL_WINDOW_FULLSCREEN));
 		}
 		else {