Parabola issue 1035 really tracks two different issues: a) contains non-free decompression engine for RAR archives, and b) support for non-free addons.

Only the latter is relevant for Debian (and therefore PureOS): RAR archive support is optional and by default disabled, and not explicitly enabled in our build routines. This can be verified by checking that build logs contain "Non-free: No" e.g. at https://buildd.debian.org/status/package.php?p=kodi

More sustainable than subscribing to a non-default repository - whether maintained by us or picking a third-party repository - is to setup a proxy for the feed which filters the repository feed and lets through only those with a license known to be Free.

Upstream repository feed:

wget http://mirrors.kodi.tv/addons/krypton/addons.xml.gz

There are 1035 addons:

zgrep -Po '<addon id="\K[^"]*' addons.xml.gz | grep -c .

Of those, 744 includes licensing field:

zgrep -Po '<license>\K[^<]*' addons.xml.gz | grep -c .

License fields are mostly Free - few are restricted to non-commercial use, and unclear:

zgrep -Po '<license>\K[^<]*' addons.xml.gz | sort -u

What about those which don't have license field?

Not sure what you are asking.

Perhaps I answered already: "[...] setup a proxy for the feed which filters the repository feed and lets through only those with a license known to be Free."

Yes, but if a plugin does not have a license tag, can we consider it public domain?

no, by default things without license are considered proprietary unless someone did investigation and put it in pd if it suits that. If you want you could try contact authors of those addons and ask them to specify license

In most of the World, copyright is automatic (i.e. there is an implicit "all rights reserved"), and as a consequence licensing must be explicit too (and arguably copyright statement must be explicit too, to be able to validate if the licensing was granted by the copyright holder and not bogusly from someone else not in possesion of rights granted).

More here (and surrounding document): https://en.wikipedia.org/wiki/Copyright#Registration

Plan: Establish a web service as a debian.net subdomain:

• Write script to strip from feed any addon not known to be freely licensed
  • • A working first draft done!
  • Write web service to host proxied+filtered addon feeds
  • Setup web service, and run filter script as cron job
  • Register subdomain for web service
  • File bugreport against Debian Kodi package with patch to use web service
  • Extend service to other addons, e.g. Hydrogen

adding @theodotos.andreou so he knows about the need of service similar to debian.net subdomain. Coordinate that together.

While we will for now remove Kodi (as it was in our default installation to showcase basically the power of Free software) because it is blocked from entering Debian testing - we will re-introduce this package with all fixes around services.

Current status:

• Exposure to non-free addons (T209)
  • Temporary workaround: Simply avoid shipping kodi in PureOS at all.
    • Pending: Unconfirmed if removal is in effect yet.
  • Solution: PureOS-forked kodi package, stripped of knowledge about problematic official Kodi addon feed.
    • Pending: Seems to need manual action to become effective.
• Provision of free addons (T208)
  • Solution: Provide manually curated feed
    • Avoided: unlikely to be maintainable.
  • Solution: Provide automatically curated feed
    • service works, but need polish (including a web page and TLS encryption)
    • addon package drafted but not yet released to Debian.