Some people use Ctrl + Shift to switch input language, some people use Alt + Shift, and I use Shift + Alt. I don't know why, I've been doing so since I was a child, and now I'm just used to it. The thing is, when you press Shift + Alt instead Alt + Shift, Windows waits for you to use some Alt + smth hotkey, and as far as I know, there is no way to prevent it from happening.
The purpose of this script is to prevent so called "ALT menu acceleration" from working when you press Shift + Alt and use Alt to switch languages while holding Shift.
Controls: Right alt + Right ctrl to turn off/on
Great thanks to TaranVH for the inspiration, he has similar script, but it works in a different way and has different usecases, he also has a lot of useful scripts, so if you're into video editing, you really should check out his YT channel and github: