This issue has been resolved and uploading is possible again. We apologize for the inconvenience.
Update · UTC
This issue is still being worked on and has been passed to the development team at our hosting provider - unfortunately, they only work on work days, so we expect the next update to be posted on Monday. We apologize for the issues and want to stress that issues like this lay outside our control.
Identified · UTC
Our investigation shows that this issue lies with our hosting provider, we're working with them to resolve this issue as fast as possible.
Investigating · UTC
We are currently investigating a high amount of image upload failures.