It’s build in in Vivaldi’s own server. You log in with your Vivaldi account. it’s not the same. Everyone can add a Mastodon instance in a sidebar (for a sidebar in FF you need an extension), but AFAIK no other browser offers a own instance by default for the user, ready to use.
It’s build in in Vivaldi’s own server. You log in with your Vivaldi account. it’s not the same. Everyone can add a Mastodon instance in a sidebar (for a sidebar in FF you need an extension), but AFAIK no other browser offers a own instance by default for the user, ready to use.