purelymail-issues Feature Request: Oauth2 for webmail

I'd like to be able to authenticate users for webmail using Oauth, to keep passwords unified across all my services. I already have an Oauth2 provider (authentik) managing auth for everything else, but my email has been left out. A quick explanation of Oauth implementation is provided by Aaron Parecki at https://oauth.net/getting-started/ Oauth2 is already supported by Roundcube, so this shouldn't be difficult to implement, though it would probably need to be tethered to a "here be dragons" warning, since you can't be expected to ensure that the oauth2 configuration for each user's webmail is correct.