The title says it all.  Only happens in some folders, v12 Patch 31.

The work around is to take a patch of the graphical query from Problem Folder, integrated it into a Known Good Folder, and after validating, copy the JSON file shown in the error from the Known Good Folder location to the Problem Folder. We did not validate the query after pasting the file to the Problem Folder, because the file is getting deleted after we validated the graphical query.  May be related - we are working out some memory issues that see to be folder specific.