There only 2 ways: rotate freely patch(es) or follow device specific settings via "default allowed orientations" patch. If you would have my patch (+orientations restricted to only inverted landscape) and latest sailfish_linux_chroot /qxcompositor then nothing should change when you rotate device (window should stay in inverted landscape) unless I mess up something. Should be fixable, just needs some debugging as I do not have gemini. No idea about harbour-containers.