We are getting a HTTP 500 error for the first requests on a fresh 2.7.7 installation and recovery with data from 2.4:
Completed 500 Internal Server Error in 179ms (ActiveRecord: 0.0ms | Allocations: 27504) NameError (uninitialized constant #<Class:#<Plugin::Instance:0x00007fe15d1f0e00>>::AvatarLookup) app/models/topic_list.rb:24:in `block in preload' app/models/topic_list.rb:24:in `preload' app/models/topic_list.rb:148:in `load_topics' app/models/topic_list.rb:81:in `topics' app/serializers/suggested_topics_mixin.rb:16:in `include_suggested_topics?' (eval):6:in `_fast_attributes' app/controllers/application_controller.rb:519:in `render_json_dump' app/controllers/topics_controller.rb:1147:in `block (2 levels) in perform_show_response' app/controllers/topics_controller.rb:1137:in `perform_show_response' app/controllers/topics_controller.rb:162:in `show' app/controllers/application_controller.rb:395:in `block in with_resolved_locale' app/controllers/application_controller.rb:395:in `with_resolved_locale' lib/middleware/omniauth_bypass_middleware.rb:71:in `call' lib/content_security_policy/middleware.rb:12:in `call' lib/middleware/anonymous_cache.rb:355:in `call' config/initializers/100-quiet_logger.rb:23:in `call' config/initializers/100-silence_logger.rb:31:in `call' lib/middleware/enforce_hostname.rb:23:in `call' lib/middleware/request_tracker.rb:177:in `call'
After some retries, the errors seem to disappear. The error can be reproduced by restarting the discourse instance. We are using the docker based Discourse installation.
Please let me know if you need further infos or let me know how I can further investigate this issue.