Mouseover for toolbar

[sarah-binf]

When I hover over the icons in the toolbar a description of what they are does not appear (versions 50.7.4 and most recent).
It does appear in the example graphs for example dotplot-1 as seen below:

Is there a way I can get this to appear? Can it be done using the events parameter and if so how?

[neuhausi]

It shows for everyone. Do you have a web page where they don't appear? It may be a css bug.