On this page:
How to delete configuration snapshots?
To delete a configuration snapshot:
Log in as a user with the Jira System Administrators global permission.
Choose the cog icon
at the top right of the screen, then choose Configuration Manager:
Select Snapshots to open the Configuration Snapshots page and choose a snapshot.
Click on the icon in the Actions column on the Configuration Snapshots page.
Choose the Delete option in the Actions box.
Confirm the snapshot deletion.
The chosen snapshot will be deleted.