Any downtime expected? A user reported a missing image recently. I thought the wiki had a hiccup. Part Measure Linear wiki page: Error creating thumbnail: File missing
I cannot attach files. I am trying to add logs to issue #4242 and issue #4243.Mantis wrote: APPLICATION ERROR #503
Invalid upload path. Directory either does not exist or not writable to webserver.
If it happens with any regularity you can open the Developer Tools in your browser, go to the Network tab, and enable keeping logs. That should let you inspect what happened after the fact.
I had this too recently. What solved the problem for me was closing and restarting the browser.