VVC (H.266) needs support in demultiplexers, primarily MP4
The InterDigital Inc. VTMDecoder VLC Plugin supports decoding of VVC (H.266) video. Fraunhofer VTM EncoderApp and VVenC are able to create video streams, as well as ultravideo uvg266 (a VVC encoder based on the Kvazaar HEVC encoder). GPAC MP4Box supports multiplexing VVC video into MP4 containers (codec FourCC "vvc1").
Unfortunately, the VLC player does not yet support playback of VVC video inside MP4 because the MP4 demultiplexer seems not to handle this video format yet. The playback shows a black screen with no specific dimensions, but the duration is as expected.
Small sample file: foreman_cif_pal.266.mp4