"3D Anaglyph Mode" Turns on After Minimizing

Yesterday my League of Legends during the loading screen after minimizing I came back to an orange tinted loading screen with a message in the bottom-right saying something like: "League of Legends Rating: Fair Some objects may be rendered at incorrect distance Press ctrl+alt+ins to toggle this message"

Once the game started I noticed the game was in 3D mode and I saw red and blue versions of everything, increasing in distance from each other based on how far they were from the camera. I would have to use the shortcut Ctrl+T to disable it every time I maximized it.

After that if I were to minimize it again I would get the same result and have to do ctrl+t again.

It's no longer happening today so I can't get a screenshot (even though I didn't reboot or update league and it was happening across multiple games and game modes).

Steps to reproduce:

1. Ensure the game is in full screen mode (didn't test other screen settings)
2. Alt+Tab to minimize the game at any point during the game or loading screen
3. Maximize the game
4. Now you're in 3D mode! It hurts your eyes!!
5. Press Ctrl+T to disable/re-enable