http DoH: make answers include access-control-allow-origin: *

Otherwise most browsers won't allow JS from other sites to use the data - one of the two primary use cases for DoH as stated in RFC 8484.

/cc @jhelebrant. I hope we haven't "forgotten" any other http feature around this.

Manually tested: the header does appear, and I can't see anything else suspicious in headers sent by some big public DoH services.

@jhelebrant Please test if it works for you, we can merge it afterwards.

Thanks, it works!

Google seems to send some additional headers, but they are not actually needed for JS/web requests and most of them are cache related…

assigned to @ljezek

assigned to @tkrizek

added 6 commits

• 6cd7b402...fd15bc6c - 5 commits from branch master
• defb65cc - http DoH: answers include access-control-allow-origin: *

Compare with previous version

added 3 commits

• defb65cc...fb8d0ca0 - 2 commits from branch master
• a34aa1ee - http DoH: answers include access-control-allow-origin: *

Compare with previous version

merged

mentioned in commit 81d78f8f

mentioned in merge request !1246 (merged)