Page titles seem pretty inconsistent on donatewiki

Viewing a normal wiki page e.g. https://donate.wikimedia.org/wiki/Support_pages, or a support page e.g. https://donate.wikimedia.org/wiki/FAQ/fr gives the page title as set by {{DISPLAYTITLE}} followed by "- Wikimedia Foundation". This seems fine.

However viewing a donation form shows the title MediaWiki:Donate_interface-make-your-donation (en = Make your donation now) followed by either "- Wikimedia Foundation" if the language is English https://donate.wikimedia.org/?uselang=en&country=GB or "- Donate" if the language is anything else (including en-gb) https://donate.wikimedia.org/?uselang=fr&country=FR

This is also the case for countries where we have a not fundraising message e.g. https://donate.wikimedia.org/?uselang=en&country=IR, despite trying to use {{DISPLAYTITLE}} to set a more appropriate title.