I found another user that was experiencing the same issues as me on reddit: https://www.reddit.com/r/unRAID/comments/1kj86vo/unraid_connect_causing_webui_issues_on_71/ The Unraid Connect plugin is the culprit. Uninstalling the Unraid Connect plugin fixed everything. Hopefully they can get these bugs ironed out with a future release.
I have the issue in both situations, updating an existing plugin from the plugins tab and from installing a new plugin from the apps tab. I think that particular screen shot is from the plugins tab if I remember correctly.
Attached is my diagnostic zip. I'll work through uninstalling individual plugins. Is there an easy way to backup / restore each of the plugins' settings?
wopr-diagnostics-20250519-1155.zip
Any chance you found a permanent solution for this? My setup just started showing this issue. Even the update plugin windows are blank. No changes to hardware or anything. I first noticed the issue on 7.1.2 so I downgraded to 7.0.1. No change. Different browsers / InPrivate modes did nothing. Everything seems to work in Safe Mode with Gui. Any chance this is the result of a plugin?