Props for P1S door and top when printing PLA (Also maybe X1 etc if they they have the same fittings?)
Deliberatly holds up top glass to the left to avoid snagging the feed.
Also left side (with door open) gives more even ventilation than opening top front IMO
Holds door open enough for good prints even with external temperature changes and so its not flapping around during printing.
(Note heated bed temp should be no more than 55 deg for PLA with enclosure and slightly propped top and doors)
Re door prop , you can slide the door prop in from the right side or attach to door frame then swivel up onto to door from below.
If you push the door prop to the left a little once fitted it will grip the door.