I use this solution in a similar way, but I usually share a single window. I use this command, change /dev/video2 with your virtual output and WINXID with the X

I use this solution in a similar way, but I usually share a single window. I use this command, change /dev/video2 with your virtual output and WINXID with the XID of the window you want to view (use xwininfo to get it). gst-launch-1.0 ximagesrc use-damage=0 xid=WINXID ! videoconvert ! video/x-raw,format=YUY2 ! videoconvert ! queue ! v4l2sink device=/dev/video2 Also, I usually combine it with scrcpy, so I can share my Android phone/tablet's screen on my computer's videoconference session.