Someone has reported the following to FSF:
The PureOS homepage has a screenshot of something called "Purebrowser", which looks like a redranded Firefox, so it seems likely that Purism is aware of the freedom issues with popular browsers and has their own alternative, which is good. However, Debian's versions of Firefox ESR and Chromium, both with known freedom issues, are present in PureOS's repo.
I am unaware of any issues with Firefox ESR violating the FSF Free System Distribution Guidelines.
We are aware of a some issues that might violate FSDG, and we are examining each of those individually.
There are reasons that users might choose to avoid Firefox ESR, and PureOS currently does not install it by default - but that is a different matter than depriving PureOS users of the ability to use that tool.
Please file a separate issue for each violation - don't assume the underlying issues are obvious.
PureBrowser was created due to trademark concern - see T11 for more details on that.