If you install AVG they can install the AVG toolbar which is not easy to uninstall. Superantispyware and malwarebytes would not remove it when I had earlier this year as I read they “overlook” some adware.
Use Adwcleaner to remove it.
https://toolslib.net/downloads/viewdownload/1-adwcleaner
PITA to find and reinstall all the add-ons/extensions that I wanted, not to mention a few other tweaks that changed eons ago, and forgot about.
I thought you had to click the “allow” button for the toolbar to be installed?