The fix for bug 239977 gave Mozilla support for tlhIngan Hol, the Klingon language. Although I’d vaguely known that some Star Trek fans spoke Klingon, I was somewhat surprised to learn that the warriors’ tongue is a well-developed language.
Klingon was invented by Dr. Marc Okrand, a linguist originally hired to create a language for those bumpy headed aliens in Star Trek III: The Search for Spock. Instead of just creating a few words and phrases, he developed grammar, vocabulary, and usage rules. Twenty years later, the language is spoken and studied by a diverse group including Trek fans, linguists, philologists, computer scientists, and psychologists. A number of works have been translated into Klingon, including some of Aesop’s Fables, Hamlet and other works by Shakespeare, and the New Testament.
The Klingon Language Institute, a nonprofit corporation, has much more information about the language. To learn more, you might start with its FAQ. I also enjoyed reading about the written Klingon alphabet.