So I have been trying to set up http2 on my nginx server for use with my personal website, however I've run into an issue concerning firefox. When I have http2 enabled, firefox will not display the page at all. In fact, it will stay on the page it previously had loaded in that tab. I've tried to do research on my own, but I've had no luck, as all solutions I've tried seem to not work.

Client Info:
Browser: Firefox 47.0
OS: Windows 10 64 bit
Website: https://www.nickwelna.com/

Server Info:
OS: Ubuntu 14.04 LTS 64 bit
nginx version: 1.10.1
OpenSSL version: 1.0.2h
Server Config: https://gist.github.com/welnanick/a492dcb0a6f4aa0c01b0a1e17e45eba2

Site works fine in Chrome (both on Windows and Android), but not in firefox (On windows nor Android). Any clues what could be going wrong?

Try this,

ssl_prefer_server_ciphers On;
ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
ssl_ciphers ECDH+AESGCM:ECDH+AES256:ECDH+AES128:ECDH+3DES:RSA+AESGCM:RSA+AES:RSA+3DES:!aNULL:!eNULL:!MD5:!DSS:!EXP:!ADH:!LOW:!MEDIUM;

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nginx for Windows http://nginx-win.ecsds.eu/

No Change. Still works in Chrome, but not in firefox. The network monitor in firefox says the GET request is completing, but the document type is plain (as opposed to html, which is what I get when I do a plain http request), and says it received no data.

Anything in the logs? (enable debug to see more)

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nginx for Windows http://nginx-win.ecsds.eu/

Which logs?

nginx logs.

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nginx for Windows http://nginx-win.ecsds.eu/

Nothing out of the ordinary. No errors or anything.

I think it has to be a config thing that firefox doesn't like, since chrome works just fine.

Did some testing:

Browsers that work:
Google Chrome
Opera

Browsers that don't work:
Mozilla Firefox
Microsoft Edge
Microsoft Internet Explorer

Would be nice if someone with a Mac could check if safari has issues. Any other browsers I should check?

Try it with a simple index.html file with one line in it.

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nginx for Windows http://nginx-win.ecsds.eu/

I will try this later, as it is just about 4:00am where I am, and I need to be getting ready for work in 3 hrs, so I need to sleep. I will update you when I test this.

Okay, so my custom 404 page works fine in firefox, decided I'd try to test that quickly before calling it a night. I will do a new gist with some changes I made in the morning, but you can see my 404 page by going to https://www.nickwelna.com/puppies.html. So looks like it might be something with the content being served having an issue. Can you look at my other ssl config settings, maybe one of those is causing issues?

From what I can see it looks like you have some links that stop FF from continuing to load the rest of the pages, maybe some external link which expects the source to be from some specific origin, look at the source from FF, you can see some parts are loaded but the page remains blank.

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nginx for Windows http://nginx-win.ecsds.eu/

Could that be because of the content-security-policy header I have? When I get a chance I'll remove that and see if it makes a difference. I'll also just double check all of my sources for scripts are https://. Its odd, because when I change the header to Content-Security-Policy-Report-Only, chrome reports no issues so.... hmmmmm.... I'll update you with what I find out.

Which also likely won't happen until my lunch break in about three hours, so look for an update then.

Found the Culprit! Like i posted earlier, turns out it was the Content-Security-Policy header doing something weird. I've commented it out for now (because I want to figure out the solution eventually), and everything works!