Gnome screen recorder does not work

Gnome 43 screenshot/screen recording tool works for screenshot, but the screen recording button is not visible. From Gnome said that the problem is Pipewire and Gstreamer. I finally got Pipewire running (at least somehow). How can I check that gnome-shell is getting what it needs and screen recording tool to work? And could the necessary staff be packed into the Gnome installation of postmarketOS (postmarketos-ui-gnome)?

OS: postmarketOS v22.06 (with GNOME 43) Device: Purism Librem 5

Please, read this thread before replying: https://discourse.gnome.org/t/screen-recording-does-not-work/12829

You need the pipewire gstreamer element in order to record the contents of the screen.

Yes, it’s by design; and, no: the button is hidden if the shell cannot create the following GStreamer pipeline:

static canScreencast() {
    const elements = [
        'pipewiresrc',
        'filesink',
        ...DEFAULT_PIPELINE.split('!').map(e => e.trim().split(' ').at(0)),
    ];
    return Gst.init_check(null) &&
        elements.every(e => Gst.ElementFactory.find(e) != null);
}

with the DEFAULT_PIPELINE being:

const DEFAULT_PIPELINE = 'videoconvert chroma-mode=GST_VIDEO_CHROMA_MODE_NONE dither=GST_VIDEO_DITHER_NONE matrix-mode=GST_VIDEO_MATRIX_MODE_OUTPUT_ONLY n-threads=%T ! queue ! vp8enc cpu-used=16 max-quantizer=17 deadline=1 keyframe-mode=disabled threads=%T static-threshold=1000 buffer-size=20000 ! queue ! webmmux';

I would recommend asking on a postmarketOS forum how to ensure that pipewire is running and can be used by GStreamer.