Binary package hint: nautilus
When moving the Nautilus window around, if any of the edges of the window is close to the edge of the screen, dragging becomes painfully slow; the amount the window moves relative to the mouse becomes drastically reduced. It's like there's some logic for 'snap to edge' that is malfunctioning. I usually run a single Nautilus instance, large enough to almost fill the screen (but not maximised). Frequently I need to move the window between my two monitors, and instead of a simple drag, the procedure is:
1. Move Nautilus window down such that none of its edges is close to the edge of the screen (i.e. so that the bottom edge of the window is safely off the bottom of the visible area)
2. Perform horizontal movement to other monitor
3. Raise window back up to desired position
At first I assumed this was something to do with the window manager, but I only see this behaviour with Nautilus and not other programs.
Ok, turns out this is misfiled. I /do/ see the same painful behaviour in other programs too. I just hadn't noticed before, because the window slowdown seems to be proportional to the fraction of monitor area filled by the window. Yes indeed. I can only think it's a misfeature in the window manager. I'd appreciate it if someone with more knowledge of Ubuntu could move this bug over to the relevant package, if such a thing is possible. Failing that, go ahead and close as invalid.