vettrock

Going out of full screen resolves this issue for me as well.  Going back to full screen and the issue returns.  I am on MacOS 10.15.7 on an iMac.

I have been having the exact same issue since a few days ago.  version 1.20.2.  My mouse works normally in the launcher, and on every other application.  In Minecraft, I can move the mouse, and highlight items.  I can navigate the menu via keyboard shortcuts.  However every time I right or left click, the game minimizes.  Additionally the scroll wheel is not functional in the game, but works outside of the game.  Unlike the other poster, I cannot get single player mode to launch, that also minimises.