In my testing, (VDR 2.20) the command vdr --genindex fails on an
audio-only recording from a radio station for example.
The index file is generated during a recording, but if deleted, vdr
itself cannot regenerate it, nor can the command line command. Kodi for
example tries to regenerate it when playing, if it's missing, and fails.
If the index is already there, it gets deleted. Is this by design, or a
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