I can finally reproduce this, but only on macOS. The behavior seems to be that a single click is enough to trigger the action (activate / deactivate), but the icon does only change on a second click.
So if the plugin is enabled:
- First click disables the plugin, but the icon stays the green check mark
- Second click enables the plugin again, but the icon changes to disabled
Indeed saving after the first clicks and reopening the options shows the plugin as disabled. I will look into this.
Also an incompatibility in the albumartist_website plugin, I will fix this also.