[chimerax-users] Render by attribute - custom rmsd

Hi, I am developing the custom plugin for sequence alignment and structure superposition, that will have it's own sequence viewer. I would like to use 'Render by attribute" feature of ChimeraX 1.16. But without using 'matchmaker ... show True' I do not have such option. Is there a way to pass the rmsd values for superimposed structures' residues to be available for 'render by attribute'? While looking through the ChimeraX source code, I have noticed that it uses Sequence Viewer headers to store rmsd, but I can not figure out how can I add such thing to my plugin. Best, Dominik