Can't upload a group avatar
Summary
I can not upload a avatar for groups. No difference between new group and editing an existing group. In both i can't upload a new avatar. The file-chooser window will be opened, i can select the file and click to open - but nothing happens then. File size is 160 KB, file-type is a png. Also tried it with an jpg.
Steps to reproduce
Create a new group or open an existing one, try to upload an avatar image.
Expected behavior
The avatar image which was choosed in the File-chooser should be uploaded.
Actual behavior
The selected file wouldn't be uploaded.
Output of checks
This bug happens on gitlab.com - Enterprise Edition 8.16.0-rc3-ee gitlab-ee@4ec848c3a18b90beb58f48c3a926a7c570df0ed5