I don't have time to look too closely into it, but my guess is that it's a bug somewhere in the parser: https://github.com/muffinista/gopherpedia.com/blob/main/pars...

The markup behind that article isn't terribly complicated, but the parser isn't perfect either. For example: https://gopherpedia.com/gopherpedia.com/Gustave_Dore has some glitches in the lead sentence.

My suspicion was that it's getting confused by the line above the intro, but I pasted the article's source code into Wikipedia:Sandbox and gopherpedia read the intro just fine. Strange!