Heya! The Mojang outro you’re seeing is FancyMenu’s Game Intro feature playing a premade animation before the normal menu loads. You can disable it from the menu bar so it no longer downloads/runs the animation, which should also restore the ability to show the menu bar with Ctrl+Alt+C.
Go to Customization → Settings → Game Intro and turn off whatever intro is configured there (or set it to “No Intro”/clear the animation). That should stop FancyMenu from downloading the frames and let the regular main menu load again.
More info is on the docs page: Game Intro.