Released v1.7.28, with some more Python 3 fixes.
This should *definitely* fix @rekishi's issues (as in, it's no longer embedding bogus data in the JSON file, which was Not Great).
Might also fix @wApdIl's issue with Kindlets.
And I also fixed Topaz handling, because by chance I happened to test on my actual KCC test device with funky formats in it ;p.
----
NOTE: You will *probably* have to *manually* delete the
kindle_collections_path_cache.calibre file at the root of your Kindle in order to fix things. Otherwise, the plugin will keep using cached but broken data

.