On every workboard on Phabricator (e.g.) for the last few hours I've been getting this error:
Unhandled Exception ("PhutilMissingSymbolException")
Failed to load class or interface "PhabricatorWorkboardViewState".
The class or interface "PhabricatorWorkboardViewState" is not defined in the library map of any loaded library.
If you are not a developer, this almost always means that a library is out of date. For example, you may have upgraded "phabricator/" without upgrading "libphutil/", or vice versa. It might also mean that you need to restart Apache or PHP-FPM. Make sure all libraries are up to date and all services have been restarted.
If you are a developer and this symbol was recently added or moved, your library map may need to be rebuilt. You can rebuild the map by running "arc liberate".
For more information, see: https://phurl.io/newclasses