Browser Toolbox’ Style Editor will frequently randomly delete the characters I have just typed while I’m still typing, and the cursor will move. (I was editing userChrome.css.)
Ctrl-Z, or Undo from the context menu, will move the page to the top.
It happens starting from the (current) version 82.0 of Firefox (stable release). It didn’t happen in the previous version. It also happened in the Developer Edition of Firefox.
Is it a bug, or can this be prevented?