I recall these used to be in a Mediawiki
page somewhere, but now I see they
are only available on GitHub?
Wikibase is in kind of a weird place being presented as both an extension to MediaWiki and
a product in and of itself. MediaWiki has a more organised setup (but only somewhat,
I've helped fill out the changes on wiki once or twice):
https://mediawiki.org/wiki/Release_notes
They look better but are ultimately similar in content (but bigger since they cover all of
MediaWiki core).
Interesting how all of them even in Master
write "This is not a release yet!", seems they
were never finalized and cleaned.
They were finalized only in the release branches/tags, by the looks of it, as part of the
release process. Perhaps "merge changelogs back to master" could be added to
it.
How reliable are they to contain all changes made?
I gather the focus is on end-user visible changes, e.g. new visible features or API
changes, especially those which might break existing code.
In particular
https://doc.wikimedia.org/Wikibase/master/php/adr_0017.html outlines the
release notes template which includes the following difference from MediaWiki release
notes:
Don't include "New developer features" or changes to "development-only
external libraries"
One main difference between MediaWiki and Wikibase is that Wikibase is an extension to
MediaWiki and our external developer community is not as big. To reduce the burden on the
team we think it's a good idea to not include these.