@reiver@reiver ⊼ (Charles) 
Oh, that's super neat! As long as I can do said Webfinger setup via a serverless function that would be easy enough to setup. Would both the 
@pojntfxFelicitas Pojtinger 🌅 and @felicitas@pojtinger.com handles keep working? Or would latter "resolve" in the client and just redirect to the mastodon.social domain as a HTTP redirect would?
Ah. You want to point @felicitas@pojtinger.com to your mastodon.social account.
From a protocol perspective you could do it, but — I think you would have to configure mastodon.social to include your acct-uri in the WebFinger response — acct:felicitas@pojtinger.com.
The mastodon.social sysops probably won't let you do that 🙂
Although it would be cool if the did it in the future
If you have a fediverse account, you can quote this note from your own instance. Search https://mastodon.social/users/reiver/statuses/116118424609135910 on your instance and quote it. (Note that quoting is not supported in Mastodon.)