Here is an use case scenario-:
An user opens youtube.com. Then searches "xyz" and starts watching a video about xyz. Now the user can't use his mouse. Preferably, I'd want that the user can't use his keyboard except 3 keys. The 3 keys are space, left and right. Once the video finishes, then automatically the cursor and keyboard gets unlocked again. This will help a lot to a "distracted user". And will definitely improve productivity and learning.
It's windows platform
It'd be great if same tool works for udemy(or any video platform) as well.