User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:50.0) Gecko/20100101 Firefox/50.0 Build ID: 20160926162149 Steps to reproduce: Open https://www.google.com/teapot while running the Network analyzer (Ctrl + Shift + Q). Website will return with Statuscode 418- I'm a teapot (Note here: I'm not entirely sure if google has a few teapots per Datacenter standing around). Actual results: When hovering over the 418 Status-code in the list of connections, The tooltip shows "No Reason Phrase". Expected results: When hovering over the 418 Status-code in the list of connections, The tooltip should show "I'm a teapot."

I'm aware that StatusCode 418 isn't officially defined by the HTTP-standard but rather by HTCPCP. The HTTP-Standard doesn't include 418 at all but there are a few webserver-variants out there, that are able to return 418. Namely: - node.js - Go lang - StackOverflow (in Response to CSRF Violations) - Google (See URL provided in report) Please note that I don't want Firefox to implement the HTCPCP-Protocol as described in bug 46647. Only the Statuscode-description should be added.

(In reply to firefox from comment #0) > Website will return with Statuscode 418- I'm a teapot (Note here: I'm not > entirely sure if google has a few teapots per Datacenter standing around). I am seeing the the website is actually returning "418 - No Reason Phrase" so, the Net works panel seems to be displaying correct info. Why we should change that? Honza

I believe this is a bug related to HTTP/2 as it has no status phrase so it's up to the client to show one. But firefox doesn't seem to provide one for certain error types. This is the case for 422 as well - which unlike the teapot one is actually an error that is used in the wild.