Safari (iPhone, MacBook) gives NSURLErrorDomain:-1017

I face the issue that Safari returns the error: cannot parse response (NSURLErrorDomain:-1017) I tested it on different iPhones and one MacBook. iPhone XS & 11 (iOS 14.3). MacBook Pro BigSur.

Google Chrome does not have this issue!

Solution 1:

What are you using to host the website? The issue is because of:

It looks like your server is offering an upgrade to HTTP/2 even though the connection is already done with HTTP/2 - which makes no sense. Not only that, it is explicitly forbidden. From RFC 7540 section 8.1.2.2:

I had a similar issue with a .NET API which was breaking only with Safari/iOS and the solution was pretty similar to HTTP/2 configuration

Please check here: https://serverfault.com/questions/937253/https-doesnt-work-with-safari

Nginx: Header unset Upgrade; does not work if you proxy your request, use proxy_hide_header Upgrade; instead.