Your browser does not seem to support JavaScript. As a result, your viewing experience will be diminished, and you have been placed in read-only mode.
Please download a browser that supports JavaScript, or enable it if it's disabled (i.e. NoScript).
After the 3rd time of my client rebooting the server this week, I decided to try my hunch.
Looks like I was right @girish ; this fixes the issue.
@import '/app/code/core/css/whatsnew.scss';
Please do the needful
@robi Looks like non-cloudron users hit the same issue - https://github.com/nextcloud/server/issues/13556#issuecomment-848314122