Can't edit an existing image due to "Error: Failed to get image to validate"

[viritys]

Someone had uploaded a titleshot as gameplay for https://gamesdb.launchbox-app.com/games/details/21980. When trying to change the image type, I got "Error: Failed to get image to validate" and it didn't let me  click "Done".

Fixed it by saving that very same image to myself and uploading it as a replacement for itself, after which it did let me change the type just fine. Just wanted to record this bug here in case it's a symptom for something bigger.

[MJF]

Same here, tried to change a fake/custom box to a fanart box from a box-front, and got the same error