Comment 2 for bug 769335

Following your described 4 steps, I can't reproduce this here. I'm using the same unity version (also with an nvidia-based gfx-card using the binary blob-driver on a 64-bit system).

Does this happen everytime you try to trigger it?

For me tooltips appear/change when I move the mouse to a (new) launcher-icon. Clicking the "Applications" icon on the launcher (called "Applications-lense" now btw) does not make its tooltip disappear. Only when I move off of the "Applications-lense" icon the toolip vanishes.