The new mouse hover over tab feature does not always work.
My monitor set to medium 125% DPI.
See attached image of the left pane.
The hover feature does not work for the 1st and 5th tabs labeled "[D:] Open" and "[D:] \" respectively. It works fine for all other tabs.
My initial SWAG is that it has something to do with the width of the tabs since those two tabs appear to be narrower that the others.