Not really a bug, not really a problem, but I'll post it.

[BobXP]

If you hold down the right mouse button and press the WinKey, Alt+Tab, Ctrl+Esc or any other combination used to minimize the game, the mouse will stick in place and you can't move it, until you go into the game again via alt+tab.

Again, not really a bug but more like an oversight when Fish made the Windows version