Suggestion about the cache folder
There's a topic in which a user suggested a way to change the cache folder by setting up a command line on the shortcut. However, I'm sure there will be people who will find that difficult to do. So I have a suggestion: why don't you add an option in the installer where the user can manually type the desired location for the cache folder and that setting to be stored in a file somewhere in %AppData%\Local\Vivaldi (or in an ini file)? Thus when creating a backup of the entire profile it will be a lot easier to have the same custom location after fresh installation of the browser (like after fresh Windows installation, for instance).