I installed Seafile 7.0.4 on Ubuntu 18.04. The default avatar is not showing up. In seahub.log I find line as below. It seems to be adding : in the url. I am using top level site, If I add a custom avatar it works fine. It is only the default avatar that has this issue.
2019-09-09 18:52:51,713 [WARNING] django.request:152 get_response Not Found: /group/1/:/media/avatars/default.png
2019-09-09 18:54:55,443 [WARNING] django.request:152 get_response Not Found: /:/media/avatars/default.png