Basically the title. This was working yesterday, showing the name of the person who modified the record most recently. Now it shows the red ! triangle and says "Invalid visual variant" in the Record Detail.
What's weirder is when you open the interface editor to try and figure out what's going on with the Record Detail, it shows the correct name.
This message will typically show when a field that was added to the interface was changed in the database, so it isn't possible anymore to render the specific field visual variant you chose originally in the interface. Typically my easiest approach to this issue is deleting the field from the interface and adding it again in the same place (basically a refresh of the field)