I accidentally deleted an indicator and want to restore it 

When an indicator is deleted, it cannot be restored, as the system does not keep a list of deleted/recently used indicators. However, if the deletion was recent and the page has not been reloaded yet, you can click the "Undo" button to cancel the action and restore the indicator.

To avoid losing your indicators and their settings, you can create custom indicator templates and use them whenever you need to.