Colorize + Rename Rigid Body Constraints
In the physics tab of a rigid body constraints you can find the whole Add-on in the panel:

1) Inspect will open a local view to show only the constraints with its objects - press again to show the view before
2) Color rigid body constraint objects will colorize the objects belonging to a constraint
3) Reset color rigid body constraints will assign the old color to the objects
4) Rename rigid body constraints will rename all selected rigid body constraints