[chimerax-users] opening multiple csx files at same time

How can you open 2 or more csx files simultaneously in order to have the all contents of both *.csx files showing and superpositioned. This can be done for opening multiple *.pdb files which then shows all the chains of all the opened files superpositioned on the same page. But when I try to open multiple csx files, the second one completely deletes and replaces the currently open csx file and deletes what was showing from the originally open csx file.