Cannot upload profile images or issue type icons

[Karsten Stork]

Hi guys,

we cannot upload images as profile pictures or issue type icons.

The dialogue pops up, I select the image, and the grey lightbox covers the screen with the spinning thing. 

The spinning never stops.

Logs show nothing.

We have set 777 on the folder, so the user/service has write access.

Any ideas?

Update: Browser console shows a "source map error 503"