From The Register:

Web browser bugs are routinely blamed for creating huge networks of compromised PCs and undermining the safety of ecommerce transactions. Now one woman says a “security bug” in Mozilla led to the break up of her engagement.

The anonymous woman shared a Windows PC with her former fiancé. Both had separate user logins on the same machine and both preferred Mozilla to Internet Explorer. All was apparently well until the woman opened up a list of sites whose password was never saved and unearthed evidence that her man was a frequent visitor of dating websites. The woman took this as evidence of infidelity and split up with the apparent love cheat. She then had the presence of mind to report the privacy flaw to the Mozilla Foundation.

Things start to become clear when you read the bug report: it looks like the old story of boy-meets-girl, boy-gets-engaged-to-girl, boy-introduces-friend-to-girl, girl-begins-to-spend-more-time-with-friend, friend-fabricates-evidence-to-make-it-look-like-boy-is-cheating-on-girl, girl-dumps-boy. As we all know, the story continues with friend-makes-move-on-broken-hearted-girl, girl-sleeps-with-friend.

I’ll let you make your own jokes about plugins and extensions.