I had the UnionFilesystems plugin installed, but the options within it were not flexible enough to meet my needs so I configured my mergerfs stuff by hand in /etc/fstab. No problems there.
Next, I uninstalled the UnionFilesystems plugin. However its icon remains in the menu under Storage and every time I open OMV in the browser it throws an error popup box that says "RPC service 'UnionFilesystems' not found" I have to clear this error to continue.
I seem to remember removing other plugins in the past and sometimes their icons would remain behind for a while as a zombie, but they would eventually disapper. But this time it klings on.
Any suggestions? I can live with reinstalling the plugin even though I will not use it if that's what it takes to prevent the error box popup.