Why is there a chromium and chromium-ffmpeg snap?

I see that chromium snap already includes libffmpeg.so:
fabian@fabian-ThinkPad-T490:~$ ls /snap/chromium/current/usr/lib/chromium-browser/libffmpeg.so /snap/chromium/current/usr/lib/chromium-browser/libffmpeg.so

How is the libffmpeg.so used by chromium snap when chromium-ffmpeg is installed?

fabian@fabian-ThinkPad-T490:~$ tree /snap/chromium-ffmpeg/current/ | head -5
/snap/chromium-ffmpeg/current/
├── chromium-ffmpeg-91124
│   └── chromium-ffmpeg
│       └── libffmpeg.so
├── chromium-ffmpeg-91696

Thanks in advance

It’s not. See the description of the chromium-ffmpeg snap, it is intended for third-party browsers that might not be allowed to redistribute the codecs themselves. Chromium doesn’t have this problem.