Thanks, Phyllis. I noticed that in .../bin/ffmpeg/plugin.opts (and also in .../ffmpeg/plugin.opts, of course) the "new in 5.0" and "new in 5.1" sections are missing. However, the new plugins in this section are loaded into CinGG and work normally. I do not understand how this could happen; perhaps I sent you the wrong file. I am attaching the correct file again.
plugin.opts.tar.gz
Description: application/gzip
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