/sidekiqを閲覧できない問題、ログアントログインで治るという情報もあります（手元で再現できてないので確認できない）
https://github.com/tootsuite/mastodon/issues/12698
github.comsolved: /sidekiq cannot be displayed after updating to rails 5.2.4.1 · Issue #12698 · tootsuite/mastodonActual behaviour An error page may be displayed when accessing /sidekiq after updating to rails 5.2.4.1. At that time, the following error is output to the server log: NoMethodError (undefined meth...