1 minute hang when trying to open a device that's already open elsewhere

I've got a couple of webcams:

$ v4l2-ctl --list-devices
Video Capture 3 (usb-0000:00:14.0-6):
	/dev/video0
	/dev/video1
	/dev/video2
	/dev/video3

Video Capture 3 (usb-0000:0b:00.0-2.4):
	/dev/video4
	/dev/video5

It looks like MS Teams has one of them open:

$ fuser -v /dev/video*
                     USER        PID ACCESS COMMAND
/dev/video4:         sam.mor    12909 F.... pipewire
                     sam.mor   525834 F...m teams

When I select this device in Cheese's preferences, it freezes for 60 seconds before telling me that the device is not available.

I guess the underlying GStreamer video source is hanging, so maybe there's not much that can be done about this. OTOH a video source hanging shouldn't cause the whole app to freeze.

I'm attaching the output of GST_DEBUG_NO_COLOR=1 GST_DEBUG='*:5' cheese -d /dev/video4 run while Teams has /dev/video4 open: cheese-debug.txt.xz