The global search does not work when a user has too many authorizations. The issue led to the message 'Search Error: No Results' being displayed in the global search box, and a force trace. The global search now returns results as expected for all users.
Upgrade to the fix version below or a higher one.
Automation.Engine 12.1.3 - estimated, planned Release date: End of September
Automation.Engine 12.2.1 - estimated, planned Release date: End of October