Firefox cofounder Blake Ross very funnily relates the story of popup blocking in Netscape 7 in a guest appearance on the Daily WTF.

It's hard for me to write a WTF, not because I can't remember one, but because I remember too many. Netscape was one giant WTF, or as they called it back then, AOL. The company had grown so inept that “WTF” became just another thing we said each day, like “Hey” or “What time is it?” or “We just lost another 5%” or “Marketing wants to replace the Back button with an ad for Bowflex”.