YouTrack provides several default workflows that cover the most general use cases. For example, workflows that automatically assign an issue to a subsystem owner or process duplicate issue.
Edit Default Workflows
You can customize the default workflows to support your actual use cases like any other workflow on your YouTrack server.
When you upgrade your YouTrack instance, updates are only applied to default workflows that have not been modified. If you want to apply updates to an edited workflow, use the Restore default workflows option. This option overwrites the default workflows with the definitions that are stored on the YouTrack server. Any changes that you have made to default workflows are lost. If you wish to keep your changes, make a copy of the default workflow with another name before you restore the default workflow definitions.