Select text containing "RFC" + 1-4 numbers, and get a context menu to the IETF's HTML version of the RFC.
Neat, huh?!
My personal favorites (right now) are RFC2068 (HTTP/1.1 "beta"), RFC2616 (the out of date HTTP spec), RFC 7231 (one of the 6 RFC2616 "upgrades"), and RFC3986 (the URI spec).
WHY U NO LINK THOZ?! 
'cause this is a test case. 😸