Description
Event Timeline
The direct request fails because there is no 404 handler. No idea why the API request fails; it returns a 404, even though the URL is correct. Maybe some sort of timing issue, with the API returning before the image is actually there?
Got confused by all the fallbacks. There are two image requests, but both for the thumbnail guessing (AJAX + direct fallback). After those fail, there is an API request (which generates the image as it should), but the image is not requested again.
This is a serious bug and should be fixed. As a workaround, I disabled thumbnail guessing, that should make the errors go away on alpha.
Mass-removing the Multimedia tag from MediaViewer tasks, as this is now being worked on by the Reading department, not Editing's Multimedia team.