Hey, saw your post about installing Alpine as a daily driver- I'm in a
similar situation and run Gentoo with Wayland.

I've had some success with the V4L Loopback device, and wf-recorder-
some combo of:

v4l2loopback-ctl set-caps "video/x-raw, width=$WIDTH, height=$HEIGHT" $device
wf-recorder --force-yuv --muxer=v4l2 --file=$device -c rawvideo -x yuv

This lets me share as a webcam, which isn't quit the same, but works.

~QP

This is very helpful, thank you. I've seen a similar "hack" solution
suggested by Zoom using OBS:

https://support.zoom.us/hc/en-us/articles/6634039380877-Sharing-your-screen-on-Wayland

I might look into that and see how well it works on Alpine.