I've googled and FAQd and experimented without success. When I have the vim editor open in an xterm window, in insert mode, and move my mouse (and focus) into another window, the vim in the original window receives some sort of escape sequence that causes it to leave insert mode and beep.
I tried starting vim without customization, and fvwm 2.6.8 and fvwm 3 with stock configuration. It seems to happen in xterm, x-terminal-emumator, terminator, uxterm, but not in rxvt. I'm on ubuntu 21.04. I've tried running "cat -v" to see if it will show me what's happening. I've tried emptying my X resources (xrdb </dev/null). If I kill fvwm and have no window manager running, it no longer happens. I can't figure out what's happening or why, or how to prevent it. Anyone have any hints? Thanks! John
