When I mouse over an item in my database, a tool tip will sometimes appear, but it's inconsistent. (Black text on a gray rectangular background.) This tool tip will occasionally disappear and reappear after a few seconds multiple times, depending on how I move the mouse or what else I'm doing (even when the mouse has not returned to be nearby the item.) It will even appear overtop in other application. The behavior is inconsistent. I have trouble reproducing it reliably, but it's pretty frequent. I have some screen shots but not sure where to post them.

This could be in part due to some sort of bug with my instance of MacOS, but it's notable that this only happens with tooltips that originate in Zotero.