I came to the conclusion a long time ago that early browser developers must have really been on quite a lot of drugs.
And the beast shall come forth surrounded by a roiling cloud of vengeance. The house of the unbelievers shall be razed and they shall be scorched to the earth. Their tags shall blink until the end of days. — from The Book of Mozilla, 12:10
No, it was just there were no PM filters.
Some recent discussion on that one a couple Advents ago: