Fedora 33 x86_64 Intel i5vPro 5300u Webkit does not force H264 on youtube. The vaapi are inactive. export GST_DEBUG="vaapi*:5,*:3" hellgate ~ epiphany 0:00:14.557313881 2 0x563d5bccef50 WARN webkitregistryscanner GStreamerRegistryScanner.cpp:87:hasElementForMediaType: All elements for caps video/x-av1 are blacklisted 0:00:17.801657083 2 0x563d5bccef50 WARN webkitregistryscanner GStreamerRegistryScanner.cpp:87:hasElementForMediaType: All elements for caps video/x-av1 are blacklisted 0:00:18.389552564 2 0x563d5c939240 FIXME default gstutils.c:4025:gst_pad_create_stream_id_internal:<appsrc0:src> Creating random stream-id, consider implementing a deterministic way of creating a stream-id 0:00:18.389883728 2 0x563d5c939120 FIXME default gstutils.c:4025:gst_pad_create_stream_id_internal:<appsrc1:src> Creating random stream-id, consider implementing a deterministic way of creating a stream-id 0:00:18.391045696 2 0x7f56bc001860 FIXME default gstutils.c:4025:gst_pad_create_stream_id_internal:<appsrc2:src> Creating random stream-id, consider implementing a deterministic way of creating a stream-id 0:00:18.391634646 2 0x7f56bc001920 FIXME default gstutils.c:4025:gst_pad_create_stream_id_internal:<appsrc3:src> Creating random stream-id, consider implementing a deterministic way of creating a stream-id 0:00:18.446124031 2 0x7f56bc001860 WARN matroskademux matroska-demux.c:1110:gst_matroska_demux_parse_stream:<matroskademux1> Unknown TrackVideo subelement 0xec - ignoring 0:00:18.596730446 2 0x7f56bc001920 WARN glwindow gstglwindow.c:323:gst_gl_window_new: Could not create window. user specified (null), creating dummy window 0:00:18.764208519 2 0x7f56bc001920 WARN GST_CAPS gstpad.c:5701:pre_eventfunc_check:<vaapidecodebin0:sink> caps video/x-vp9, width=(int)854, height=(int)480, framerate=(fraction)30/1 not accepted 0:00:18.764292080 2 0x7f56bc001920 WARN decodebin gstdecodebin2.c:2564:connect_pad:<decodebin1> Couldn't set vaapidecodebin0 to PAUSED 0:00:18.836221616 2 0x7f56bc001920 FIXME videodecoder gstvideodecoder.c:1052:gst_video_decoder_drain_out:<vp9dec0> Sub-class should implement drain() 0:00:18.836337902 2 0x7f56bc001920 FIXME videodecoder gstvideodecoder.c:1052:gst_video_decoder_drain_out:<vp9dec0> Sub-class should implement drain() 0:00:18.894379631 2 0x563d5c938de0 WARN audio-resampler audio-resampler.c:274:convert_taps_gint16_c: can't find exact taps 0:00:18.898247096 2 0x563d5c925760 WARN audio-resampler audio-resampler.c:274:convert_taps_gint16_c: can't find exact taps 0:00:18.900984426 2 0x563d5c925760 WARN audio-resampler audio-resampler.c:274:convert_taps_gint16_c: can't find exact taps 0:00:18.954512934 2 0x563d5c938cc0 WARN videometa gstvideometa.c:414:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (928) is different from the one computed from the alignment (856) 0:00:18.956125474 2 0x563d5c938cc0 WARN videometa gstvideometa.c:414:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (928) is different from the one computed from the alignment (856) 0:00:22.582394775 2 0x563d5c938cc0 WARN videometa gstvideometa.c:414:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (928) is different from the one computed from the alignment (856) 0:00:22.612887639 2 0x563d5c938cc0 WARN videometa gstvideometa.c:414:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (928) is different from the one computed from the alignment (856) 0:00:22.646505536 2 0x563d5c938cc0 WARN videometa gstvideometa.c:414:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (928) is different from the one computed from the alignment (856) 0:00:22.679797503 2 0x563d5c938cc0 WARN videometa gstvideometa.c:414:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (928) is different from the one computed from the alignment (856) 0:00:22.712612304 2 0x563d5c938cc0 WARN videometa gstvideometa.c:414:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (928) is different from the one computed from the alignment (856) 0:00:22.748589365 2 0x563d5c938cc0 WARN videometa gstvideometa.c:414:gst_video_meta_validate_alignment: Stride of plane 0 defined in meta (928) is different from the one computed from the alignment (856) >
<rdar://problem/72597334>
As far as I know, the request of an specific video codec depends on the client (in this case the javascript code in page) Besides, certain vaapi drivers implement vp9, then it's used if so.
Indeed. I'm not sure we can do much about this issue.