GrowthExperiments needs a map of ORES topics into the more-generic topics set it uses to power its topic matching. Currently, this is backed by https://www.mediawiki.org/wiki/MediaWiki:NewcomerTopicsOres.json, which is accessed through CommunityConfiguration 1.0 code centrally from MediaWiki.org. To make ourselves able to remove legacy CommunityConfiguration code, we need to ensure the ORES topics are loaded in a different way.

There are two options we can consider here:

1. Keeping the current location, and adding support for external page titles to MediaWiki-extensions-CommunityConfiguration: This would likely mean introducing a HttpStore in MediaWiki-extensions-CommunityConfiguration and using it to load the data from MediaWiki.org (where it currently is).
2. Moving the ORES mapping to server configuration instead: It likely does not make much sense to have this config on-wiki anyway (if we look at the page history, we can see can see it was only ever edited by the Growth-Team), and using CommunityConfiguration for centrally managed configuration (for all wikis in a family) is something that we did not design for yet, so it might not be a good idea to do that with the current tooling.

Those two options were briefly discussed in T359185#9790649 et seq.