Isolate Warnings is a great free add-in made by Archisoft. It allows you to visualize warnings in a Revit model. It is the third free add-in we are exploring this month.
Warnings can severely impact the performance of your model if left unchecked. The default tools to help you solve warnings are not very good, so add-ins can help.
Download the add-in here: Isolate Warnings Add-in