Rating a song overwrites flac tags on file system

[SimonTeixidor]

Perhaps my use case is a bit strange. I'm doing this:

• Load a flac file into deadbeef and start playing
• Do some tag edits outside of deadbeef. For example:

$ metaflac --set-tag=TEST=1 01*.flac
$ metaflac --show-tag=TEST 01*.flac
TEST=1
$

• Rate the song using this plugin
• The TEST tag is now removed:

$ metaflac --show-tag=TEST 01*.flac
$

I would expect the TEST tag to remain at this point. I'm not sure if this is a bug in the plugin, a bug in deadbeef, or some limitation in the plugin API?