Can someone just do this? It's quite simple maintenance that need no more expertise than a power user.

You can submit a patch to the operations/puppet repo if you want to speed things up. See the tutorials for Puppet and Gerrit.

@Viztor: If Debian packages exist, feel free to propose a patch in Gerrit: The files to edit are https://phabricator.wikimedia.org/source/operations-puppet/browse/production/modules/mediawiki/manifests/packages/fonts.pp and https://phabricator.wikimedia.org/source/mediawiki-config/browse/master/fc-list

Change 528279 had a related patch set uploaded (by Viztor; owner: Viztor):
[operations/puppet@production] Add fonts-noto-cjk-extra, replace fonts-noto-cjk

https://gerrit.wikimedia.org/r/528279

Looks like the font is already installed in T184664, but its CJK variations weren't included in fc-list. I'm not sure it seems we're running on Stretch? fonts-noto-cjk on Buster also includes Noto Serif CJK, in addition to Noto Sans CJK.

Note: Google Noto Sans/Serif is the same as Adobe Source Sans/Serif

Change 528290 had a related patch set uploaded (by Viztor; owner: Viztor):
[operations/mediawiki-config@master] Add Noto Sans CJK + Noto Mono CJK fonts

https://gerrit.wikimedia.org/r/528290

In T226633#5394959, @Viztor wrote:

Looks like the font is already installed in T184664, but its CJK variations weren't included in fc-list. I'm not sure it seems we're running on Stretch? fonts-noto-cjk on Buster also includes Noto Serif CJK, in addition to Noto Sans CJK.

@Viztor: We're currently running the Mediawiki servers on Stretch, but if we needed there's also the option to backport fonts-noto-cjk from Buster to our internal repository.

In T226633#5395495, @MoritzMuehlenhoff wrote:

In T226633#5394959, @Viztor wrote:

Looks like the font is already installed in T184664, but its CJK variations weren't included in fc-list. I'm not sure it seems we're running on Stretch? fonts-noto-cjk on Buster also includes Noto Serif CJK, in addition to Noto Sans CJK.

@Viztor: We're currently running the Mediawiki servers on Stretch, but if we needed there's also the option to backport fonts-noto-cjk from Buster to our internal repository.

It would be best if we can do that, Noto/Source Serif CJK is the most comprehensive free serif CJK font available out there as of now. It would also be sweet if we can also back-port fonts-noto-cjk-extra which includes addition font-weights. I'm just not sure how we should do that though.

In T226633#5395538, @Viztor wrote:

It would be best if we can do that, Noto/Source Serif CJK is the most comprehensive free serif CJK font available out there as of now. It would also be sweet if we can also back-port fonts-noto-cjk-extra which includes addition font-weights. I'm just not sure how we should do that though.

fonts-noto-cjk and fonts-noto-cjk-extra are two binary packages built from the same source package (see https://en.wikipedia.org/wiki/Debian_build_toolchain#debian/control) for context. This means that if we build the package from Buster for Stretch both would be upgraded. We currently don't use fonts-noto-cjk-extra on the Wikimedia production servers, though. Is that something that should be considered independently of the backport?