When in fullscreen, mouse clicks drop FPS

Hi, as the title suggests, when I put the game into fullscreen, any left or right mouse click drops my FPS suddenly. When I place the game into windowed mode, it does not get this fps drop from left or right mouse click input.

Hi, I have this exact same problem 3-4 years later. Does anyone know why this happens? It’s nothing to do with resolution or graphics, it happens even when I set everything super low. The only solution is windowed mode, rather than fullscreen, which I guess I’ll do but it’s kind of annoying.

Edit: I solved this by checking the Max Foreground FPS option and setting it to 60.