I've been meaning to document this for a while. If you're finding yourself visiting Special:Export/Import often for the purpose of MediaWiki development there is a much better way to get content into your local wiki for testing purposes.
This short video explains how MobileFrontend extension provides tooling to help you debug live on-wiki content via $wgMFContentProviderClass [1] https://youtu.be/uRQzjN0hBlY
Hope it saves someone lots of time!
[1] https://github.com/wikimedia/mediawiki-extensions-MobileFrontend/blob/master...