I understand that there are NO "perfect fixes" here.
X11 has issues, Wayland has WAY more issues. Any Linux video stuff has issues. Win 3.11 is really not a viable option .....
I'm just trying to find the "best" way to MY particular goal of the week. "Best" does NOT mean re-writing half the OS or X11 ........
I've tried several approaches using Python/OpenCV. Too much buffering - which is basically impossible to turn off ... the designers "made a decision" long ago.
Going around buffering by downloading cam stills with wget/curl to a file and then just using OpenCV for its handy crop/resize/display trix ... wget and curl are TOO SLOW plus I get way too many partial frames. NOT sure how Motion (usually) detects a 'complete' JPG. Must read 'em byte by byte ... which ain't easy from a remote http device.
So ... what I was trying to get away from ... gonna have to use a BROWSER reading Motion streams plus kinda ugly. hard to tune, WebKit stuff to do the cropping/resizing/placement. I've used Chromium in the past, with a few tweaks to get past stupid error/debug messages. I'll just recycle the old web pages I'd made for Chromium a bit, and feed it Motion mjpeg frames directly into iframes. Kinda clunky, but I think it'll be the superior result.