I found recently that strange thing is happening when I right click on selected script or layer in a table of content. Some items of pop-up menu are faded:
If I repeat right click 3 or more times, they become available. Another option is keyboard shortcut Shift+F10, which is far from ideal. It happens on a long lists, e.g. over 15 layers in the table of content.
I am using ArcGIS 10.5.1 and I have a suspicion that this is yet another windows update, the latest I have is "Feature update to Windows 10, version 1903", early September.
This is not happening in other applications, e.g. explorer. It seems specific to ArcGIS. It looks like a minor thing, but I found it very annoying.
Are you experiencing this behavior and hopefully know how to fix it?