Custom navigation links are menu links that can be added to Help Center's header. In the following screenshot, Return to Timelapse and Write us an email are custom navigation links.

To create a navigation link, head to Help Center Settings and select the Navigation Links tile.

From this screen, you can change the order of the links or create a new navigation link.

Click + New Navigation Link to create a link.

The link title is what will be visible on your site's header and the destination URL is where you want to send visitors when clicking on the link.

The destination URL can also be a mailto link if you want to link to an email address.