Just for posterity: It was solved on sv-wikt by using templates that automatically categorize correctly:

@MarcoAurelio, thank you! I've added this description to the translation docs.

The header was set during session_start(). I changed it by setting session_cache_limiter().

Yes, that's correct: I'm using Safari on Iphone. I explicitly chose the desktop version of the site.

@Framawiki, I'll clarify: The problem exists on mobile Safari. Firefox works as expected.

Firefox bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1321792

Background on the URL:

In T186976#3960941, @Zoranzoki21 wrote:

Hi, for each configuration on wikis, we need community consensus. Please, provide link to it, or start rfc there. Thanks!

@Od1n , I didn't see your comment from November.

I figured out how to do this with the title blacklist:

This seems to work as expected now, probably because the canonical URLs were changed to https:// a while back.

@Dereckson Correct - the categories haven't changed since I made the original request.