How to get rid of? Not in http://eraseviruses.com/how-to-get-rid-of-bestapplicationdownloads-com-completely/ There is no "default settings" used by the Chrome entry...
Your question has nothing to do with Vivaldi Browser. Vivaldi is not a malware-removal software, and it does not contain malware like bestapplicationdownloads.
Don't know if it works, but that Chrome Reset Button can be accessed in Vivaldi by entering the url
I would have thought a better way would be to use a fresh profile (but this means re-adding extensions, bookmarks and passwords, of course).