Tooltips come up as you mouse over the project name in the list. When perusing a list of names it becomes quite annoying as it can partially cover text you are trying to scan.
This could be helped a lot but only showing the tooltip if the project name is truncated. The full project name is visible for all of my projects so the tooltip serves no purpose other than to annoy me.
In my opinion, it would be better to subtly highlight the project name over mouseover and then only show a tooltip when hovering over a project name for more than about 800-1000ms.