I've just run into an issue that is affecting all web applications on my farm. It's only affecting SharePoint List as document libraries seem to be fine.
This has been tested by multiple users with different browsers on every web application in the farm. The same issue persists.
Any time we try to use the ribbon on a list item, the ribbon is mostly disabled (see image).
I know it's not a permissions issue because I can click the Title link to view/edit the item. I can also use the Quick Edit button to view/edit items. None of the items have unique permissions. I've personally tested with both a site collection admin account and the farm account.
It's not a show stopper as I can use these workarounds, it's just annoying that the ribbon isn't working.
Has anyone seen this type of ribbon corruption?