If you are using containers, New container tab [0] and Switch Container [1] were essential add-ons. Now with this feature built-in, the latter is unnecessary.
Now all we need is something to let us map shortcuts to open specific containers, e.g. alt+s to open a new tab in the shopping container. (I tried using Application Shortcuts on OSX, but a. they stop working after restarting Firefox and b. they don't work if a tab has full screen video because that hides Firefox's menu bar on all monitors.)
> “Reopen in Container” tab menu option appears for users with Containers that lets them choose to reopen a tab in a different container
This is going to make containers even more useful.