Makes sense, it seems like you never had run the post-migrate to remove the columns that were originally there, which I removed in DEV: Re-add polymorphic bookmark columns by martin-brennan · Pull Request #16261 · discourse/discourse · GitHub. I may just need to check for the columns before re-adding them here discourse/db/migrate/20220322024216_add_bookmark_polymorphic_columns.rb at 037172beaae0743176eee653bd2cd4cd1ce5c7e9 · discourse/discourse · GitHub , will make a commit for that.