❯ ffprobe 4.webp -hide_banner
[webp @ 0x562a123f7900] skipping unsupported chunk: ANIM
[webp @ 0x562a123f7900] skipping unsupported chunk: ANMF
[webp @ 0x562a123f7900] image data not found
[webp_pipe @ 0x562a123f67c0] Could not find codec parameters for stream 0 (Video: webp, none): unspecified size
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
Input #0, webp_pipe, from '4.webp':
Duration: N/A, bitrate: N/A
Stream #0:0: Video: webp, none, 25 fps, 25 tbr, 25 tbn
If you ignore the errors these are mostly the same, but there are some minor differences, and the errors might actually tell us something about how fluxer is interpreting these files.
In any case, I can reproduce the issue so I'll pass this along.
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