The contributions popup appears immediately as it's hovered and then stays in place for several seconds. It's very easy to hover it by mistake, for instance when moving the cursor towards the browser tabs or towards the skin tabs (especially in Vector where they're on the right side). I'm often disturbed by this visual glitch. See screenshot (in which the cursor was on the Phabricator tab).
Possible solutions include
- add a minimum delay before showing the popup, so that it doesn't appear when the cursor very quickly passed above the contribution link;
- show it for a much shorter time when the cursor moves out of it.