Using Mastodon as an auth provider


I am using Gitea Version: 1.14.0+dev-537-g84b147c7f

I have been trying to setup Mastodon as my auth provider. Inside the Mastodon admin panel, I went into </>Development and created a new application. It gave me the Client key, Client secret and access token.
I set the Application name to “Gitea integration”, and for application website, I tried both the URL for my Mastodon and Gitea install.

For the redirect URI I set to: urn:ietf:wg:oauth:2.0:oob

In the Gitea admin panel, I have added Mastodon under authentication sources I have entered the Client ID (Key) and the Client Secret. It does not ask for the token.

I just set the icon URL to …logo_full.97822390.svg
and the authorize URL to

“Use URL custom URLs instead of default URLs” and “This Authentication Source is Activated” are both checked.

When I try logging into Gitea through mastodon I get to the Mastodon login screen. After trying to login I get the following: The redirect uri included is not valid.

Screenshot from 2021-01-20 20-59-04

Any suggestions? I am very thankful for this new feature and very excited about being able to use it. Thank you.