Sometimes, if a window is at the edge of the screen, it prevents x2x from moving control to another other computer. Same problem with x2vnc.
I tried adding these lines to my config, yet the problem still occurs. EdgeThickness 0 Style x2x* Sticky, StaysOnTop Style x2vnc* Sticky, StaysOnTop This problem does not occur until some time after fvwm is restarted, and I have yet to determine exactly when it does.