feature request (add custom map layer) for geometry viewer panel

Dear Developers,
I've noticed recently that the geometry viewer panel has been added to the
panel list, which can be used to check polygon or point in a convenient
way. But there is a little problem when using the feature in China. As most
people known, the coordination in China has some offset, as a consequence,
the point in the map was not at its exact position when using the
coordination in OpenStreetMap which is the build-in map in PgAdmin.
I found that PgAdmin is using the leaflet as its map api, which could add
layers as the user need. I want to add Chinese Compatible layer (like
autonavi.com) to PgAdmin Geometry viewer panel, is there any convenient
method to do that? (As far as I known, the only way is to modify file
"/web/pgadmin/static/js/sqleditor/geometry_viewer.js" to achieve this)

Thanks very much.
August White