It must be something with OS X.
I'm running OS X Yosemite with the latest versions of Safari, Firefox, and Chrome. Results:
Chrome:
Both https://alpha-labs.net/2014/12/openfire-and-ciphers/ and https://edit.alpha-labs.net/p/7zD6BfcAld
https://edit.alpha-labs.net/p/7zD6BfcAld give "Your connection is not private, NET: ERR_CERT_INVALID"
Safari
Both https://alpha-labs.net/2014/12/openfire-and-ciphers/ and https://edit.alpha-labs.net/p/7zD6BfcAld
hang indefinitely
Firefox
https://alpha-labs.net/2014/12/openfire-and-ciphers/ gives 400 Bad Request
https://edit.alpha-labs.net/p/7zD6BfcAld actually works!
So, you are 1/6 here running some of the most commonly used browsers. Can't test Internet Explorer because ... OS X.
I tried on a Windows 7 machine and it worked in every browser just fine!