All of a sudden I can no longer edit or view list items using the items tab. I have full control of the site and I also added myself as a SCA. I verified my permissions in Library permissions. Item-Level Permissions are Read Access: Real All Items; Create and Edit access: create and edit all items. Appears to be an issue with all lists and library. Also, all controls on the list tab are grayed out until I deselect the item and reselect. Could there be an issue with a recent SharePoint patch?
Yes. This issue exists in the recent sharepoint 2010 patch.
A fix for this issue was released by Microsoft on 27 April 2020.
To troubleshoot this make sure – that particular user has at least READ access to the Master Page Gallery library – you will find this from the site settings page -> Web Designer Galleries section (to get this option listed, you need to activate the SharePoint Server Publishing Infrusture feature).