Thunderbirdhas got a spaces toolbar to quickly switch between different tabs and Vivaldi allows us to put websites in its sidebar. These are very useful features so Firefox should have something like this for Firefox Relay or Mozilla VPN.
At the moment the sideview function of the browser is very limited and the extensions of the browser do not work with the sideview (ad blocker for example)
1. Would be great to enable the sidebar/sideview or disable it from the menu for those who do not use it.
2. Add features/extensions in it similar to Vivaldi. Mozilla products like Firefox Relay and a free version Mozilla VPN as well as Pocket
3. Overall would be nice if it were more like the sidebar on Vivaldi instead of a tab for bookmarks or a small separate tab