Comment 36 for bug 1988488

I think the problem is gnome-shell waiting for this command (which never finishes):

/usr/lib/x86_64-linux-gnu/gstreamer1.0/gstreamer-1.0/gst-plugin-scanner -l /usr/bin/gnome-shell

because it's waiting for an X server (which does exist as Xwayland):

#0 0x00007f76ea710ec4 in __GI___poll (fds=0x7ffed6d30280, nfds=1, timeout=-1) at ../sysdeps/unix/sysv/linux/poll.c:29
#1 0x00007f76e9c78e23 in ?? () from /lib/x86_64-linux-gnu/libxcb.so.1
#2 0x00007f76e9c7c522 in xcb_connect_to_fd () from /lib/x86_64-linux-gnu/libxcb.so.1
#3 0x00007f76e9c7cedc in xcb_connect_to_display_with_auth_info () from /lib/x86_64-linux-gnu/libxcb.so.1
#4 0x00007f76e9e57eea in _XConnectXCB () from /lib/x86_64-linux-gnu/libX11.so.6
#5 0x00007f76e9e47d17 in XOpenDisplay () from /lib/x86_64-linux-gnu/libX11.so.6
#6 0x00007f76ea37c537 in ?? () from /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvaapi.so
#7 0x00007f76ea353d28 in ?? () from /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvaapi.so
#8 0x00007f76ea3181f7 in ?? () from /usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvaapi.so
#9 0x00007f76eaae85c5 in ?? () from /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0
#10 0x00007f76eaaef84d in ?? () from /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0
#11 0x00007f76eaaf08f4 in ?? () from /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0
#12 0x00007f76eaaf19b8 in _gst_plugin_loader_client_run () from /lib/x86_64-linux-gnu/libgstreamer-1.0.so.0
#13 0x000055c6eaeb61dc in ?? ()
#14 0x00007f76ea623510 in __libc_start_call_main (main=main@entry=0x55c6eaeb6120, argc=argc@entry=3,
    argv=argv@entry=0x7ffed6d30c98) at ../sysdeps/nptl/libc_start_call_main.h:58
#15 0x00007f76ea6235c9 in __libc_start_main_impl (main=0x55c6eaeb6120, argc=3, argv=0x7ffed6d30c98, init=<optimised out>,
    fini=<optimised out>, rtld_fini=<optimised out>, stack_end=0x7ffed6d30c88) at ../csu/libc-start.c:381
#16 0x000055c6eaeb6235 in _start ()