On projects that use Gin as a site wide theme, there is no region to place a site wide menu for navigation.
I have many projects where the content is data oriented and essentially the whole thing is an admin site. Gin works well and users have a consistent UX with editing, viewing, and views generated dashboards, etc. However, there is no easy way to place a site nav menu block that displays consistently on admin and content pages.
Perhaps a region defined for a menu block or a separate module like Gin Toolbar dedicated for a menu?
Closed: won't fix
3.0
Code
Is this what you're looking for? #1869638: Make the menu shown in the administration menu tray configurable →
Closing as the mentioned linked issue might be what you're looking for.