MP4 how to play?

How do I play mp4 files on OpenSUSE 15.3?

Assuming that, the MP4/H.264 Videos (HTML5) shall be played with Firefox, this SDB – <https://en.opensuse.org/SDB:Firefox_MP4/H.264_Video_Support&gt;.

Thanks for the answer.
I ran the line below and everything was resolved

sudo zypper in --from packman ffmpeg gstreamer-plugins-{good,bad,ugly,libav} libavcodec-full

You can actually open .mp4 files (files on your system) with Firefox
I was doing it myself for while because the picture in picture mode gave borderless playback which was useful for some hosting I was doing in Zoom
But now I use mpv

Running the above command results in installation of a bunch of packages, which aren’t needed. This works for now, but is prone to future annoyances:

**Leap-15-3:~ #** zypper install --from packman ffmpeg gstreamer-plugins-{good,bad,ugly,libav} libavcodec-full            
Loading repository data... 
Reading installed packages... 
'libavcodec-full' not found in package names. Trying capabilities. 
'libavcodec57' providing 'libavcodec-full' is already installed. 
'libavcodec58_134' providing 'libavcodec-full' is already installed. 
'ffmpeg' not found in package names. Trying capabilities. 
'gstreamer-plugins-good' not found in package names. Trying capabilities. 
'gstreamer-plugins-good' is already installed. 
Resolving package dependencies... 

The following 39 NEW packages are going to be installed:
  ffmpeg-4 gstreamer-libnice gstreamer-plugins-bad gstreamer-plugins-bad-lang gstreamer-plugins-libav gstreamer-plugins-ugly gstreamer-plugins-ugly-lang libIexMath-2_2-23 libImath-2_2-23 libSDL2-2_0-0 libSoundTouch0 libavdevice58_13 libcdio19 libgssdp-1_2-0 libgstadaptivedemux-1_0-0 
  libgstbadaudio-1_0-0 libgstbasecamerabinsrc-1_0-0 libgstcodecparsers-1_0-0 libgstisoff-1_0-0 libgstmpegts-1_0-0 libgstsctp-1_0-0 libgsturidownloader-1_0-0 libgstwayland-1_0-0 libgstwebrtc-1_0-0 libgupnp-1_2-0 libgupnp-igd-1_0-4 liblilv-0-0 liblrdf2 libmms0 libmpcdec6 libnice10 libofa0 
  libserd-0-0 libsord-0-0 libspandsp2 libsratom-0-0 libsrt1 libsrtp2-1 libzbar0 

39 new packages to install. 
Overall download size: 6.3 MiB. Already cached: 0 B. After the operation, additional 13.7 MiB will be used. 
**Continue? [y/n/v/...? shows all options] (y): **n 
**Leap-15-3:~ # **

Users may want to use a minimal procedure: https://forums.opensuse.org/showthread.php/540572-Installing-Packman-Codecs?p=2938992#post2938992