multi account containers: support "always open this site in Default Container"

[dangbert]

Regarding multi account containers in firefox, it's possible to assign a site to always open in "whatever container", but it's currently impossible to do this for the "Default Container".  The workaround is to either copy the current URL and open a new tab, or to use the extension to "Reopen this site in..." > "Default Container".

But it'd be nice to add support to autmatically open a given site in the "Default Container".  For example, I want this for GitHub, often I get to a link via Google (which I have as its own container), and want to instead see the site in the default container.

Link to repo for reference: https://github.com/mozilla/multi-account-containers

[dangbert]

I could potentially do this myself with a little bit of support / guidance on how to get started. (I've done web development but never edited a Firefox extension).

[dubdubdubdubdub]

I need this as well, I accidentally set duckduckgo to a container but I can't revert it back to the default container. Extremely frustrating.