Conversations involving multiple participants, allowing collaboration and information sharing in Teams
Yep - exactly the same issue here. Nothing fancy with my setup either - an i7 laptop running the latest release of Windows 10 with a USB wired mouse and keyboard.
Randomly stops accepting left and right arrow inputs into the text window. Literally switch to any other opened app and the arrow keys behave as they should. Switch back to Teams - nothing.
I also have an extremely annoying copy & paste issue into Teams that randomly works when it wants. Again, any Clipboard contents continue to work fine when injected into the likes of Word, etc.
It wouldn't annoy me so much if I didn't have to use Teams on a daily basis.