In OBS: Sources → + → Browser, untick Local file, paste the URL, size it —. It refreshes every 30s. To start a new session, right-click the source → Interact and double-click the session.

Live run is on, so this URL is served by the helper on your PC: start live/mcsr-live.py, then add a Browser source with it, size —. The size leaves room for the run.

Runs from the helper on your PC, not this site: start live/mcsr-live.py, then add a Browser source with this URL, size — at 100% transform. Use Scale to resize it.