* Use ErrorsController to render error pages
* Hide GitHub bug report prompt from anything other than dev.to and forem.dev
* Update service worker to use 404 and 500
* Other fixes
* Initial work for streaming app shell way of using serviceworkers
* Close in on serviceworker adjustment finalization
* Add docs and loading indicator
* Remove useless code
* Don't run on API
* Update app/javascript/contentDisplayPolicy/hideBlockedContent.js
* Fix small details
* Don't run serviceworker.js code in test env
* Fix JS in serviceworker
* Move private keyword to proper place in async controller
* Change shell_version to HEROKU_SLUG_COMMIT
* Update caching config
* Add test for async_info/shell_version
* Move validations from controller to model
* Add new columns to feedback message model
* Use polymorphic notes relationship
* MVP of ticketing system
* Use new URL for reported_url param
* Add missing files
* Add validations and tests for feedback_messages
* Clean up some html
* Update create spec and add update spec
* Add mail tests and lint
* Add link to user profile
