Items as of Oct 2020; things might have changed once actionable in ~2022.
* Make "Developers" link in mediawiki.org footer link to DevPortal:
** Since https://www.mediawiki.org/wiki/Requests_for_comment/Add_developer_link_to_footer_of_Wikimedia_wikis , mediawiki.org has a link in the footer called "Developers" which (ironically) links to https://www.mediawiki.org/wiki/How_to_contribute which is //not// developer specific at all. Instead, link to Developer Portal once existing. Same on other wikis like https://wikitech.wikimedia.org/wiki/MediaWiki:Sidebar
* Add yet another item to https://www.mediawiki.org/wiki/MediaWiki:Sidebar (or remove some)?
* Update links and content on https://www.mediawiki.org/wiki/How_to_contribute : It links to https://www.mediawiki.org/wiki/Special:MyLanguage/API:Web_APIs_hub which isn't too great.
* Decide what [not] to do with https://meta.wikimedia.org/wiki/Wikimedia_Resource_Center/For_developers (but also see T143629), may want to either link or simply redirect or whatever.