Hi
I think I remember that happening to me.
I believe that it was a third party adware program of some sort.
Check your startup items with CCleaner and see if you can identify it and turn it off.
If you can do that, you can probably find it and unistall it.
You might try running Malwarebytes and see if it shows up as a PUP.
Mike
PS.
Web Bar Removal Guide
Web Bar - Uninstall
Web Bar Adware