Trouble signing commits with SSH keys

Gitea 1.16.0 added support for signing commits using an SSH key. Unfortunately, I can’t get gitea (I’m runing ersion 1.17.2) to verify my signature:

I have added my signature to Settings → SSH/GPG KEys already

Am I missing something?

I had the same issue. Verifying the key by signing a string from gitea in Settings → SSH/GPG Keys fixed it. Now the signature is displayed as valid.