A dialog sayigg “Select the authentication method you used when registering: Fediverse Account (Mastodon, Pixelfed, …); Verify your identity by sending us a message from your Fediverse account.
And in the handle input field, it says https://mastodon.xyz/@Profpatsch with a big “verify my identity” button
Screenshot of a "Block User" UI in Flohmarkt. A text input contains "https://mastodon.xyz/@Profpatsch" with a green "Block User" button. Below it, a blue
info box shows "Already blocked user https://mastodon.xyz/@Profpatsch as
Profpatsch@mastodon.xyz". A "Blocked Users" section lists three entries:
midzer@chaos.social, marc_uwe_kling@tube.funfacts.de, and Profpatsch@mastodon.xyz, each with a green "Unblock" button.
You can now use a fediverse profile URL anywhere you need to refer to a fedi account, in addition to a handle on #flohmarkt
Tested with #Mastodon, #Akkoma, #Pixelfed, #Peertube