Draggable overlay :

So you can drag the overlay. Why? Because currently, the overlay is below the chat. Or it's to hard to implement. Maybe just add a config that let you set the x and y of the overlay

Overlay format :

So you can set the format of the overlay. This is the available option :

%name is for the name
%description is for the description
%x is for the x
%y is for the y
%z is for the z

And the default format is :

%name @ %x %y %z

Copy button :

So there is a copy button when you highlight the coordinate. And there is a config for the format. The available option and the default format is the same as the overlay format. See above (Overlay format) to see the option and the default.

The latest commit (234d3cf) adds the overlay positioning configuration screen, it is a simple X and Y config.

The next latest commits now add a overlay format and copy button, not implemented to all the specifics that are detailed here, but close enough that I feel comfortable closing the feature request.