"client is not authorized" after update to Gitea 1.15.0


yesterday Gitea 1.15.0 was released, so I decided to update. However, since that release my Drone builds stopped working (or the webhooks, to be more precise). In the page for the webhook settings I only get the following output:

I already checked my Client ID and secret, but it still won’t work. I’m assuming the new Gitea version changed some of the webhook logic, since it used to work before the update without issue.

Does anybody have the same problem or know how to resolve it?

It seems the login to Gitea fails, I have the following messages in my log:

{"level":"error","login":"Sunner","msg":"cannot update user: pq: value too long for type character varying(500)","time":"2021-08-23T15:24:56Z"}
{"admin":true,"error":"client is not authorized","level":"warning","msg":"api: cannot sync repository permissions","name":"[REDACTED]","namespace":"Sunner","read":true,"request-id":"1x8MWwQ2eQJxxePFvT90fTpi5CH","time":"2021-08-23T15:24:57Z","user.admin":true,"user.login":"Sunner","write":true}
{"admin":true,"error":"client is not authorized","level":"warning","msg":"api: cannot sync repository permissions","name":"[REDACTED]","namespace":"Sunner","read":true,"request-id":"1x8NQIR4vahzUnTj3hYKVIgEZyO","time":"2021-08-23T15:32:17Z","user.admin":true,"user.login":"Sunner","write":true}

The relevant fields in the Drone DB that I can find with type varchar(500) are user_oauth_token and user_oauth_refresh

Appearently you need to manually edit the Drone DB for Gitea to work as described in Add asymmetric JWT signing by KN4CK3R · Pull Request #16010 · go-gitea/gitea · GitHub. After that it works