100% CPU use when using NoSquint and an Adblock Plus filter

[garyking]

This is a relatively specific bug, but I figure I'd report it anyway.

Follow these steps to reproduce the bug:

1. Install AdBlock Plus.
2. Install Fanboy's Social Blocking List (you can do it via here; click the link that says "open this dialogue").
3. Visit an Apple Support page, such as this one.
4. Zoom in/out, so that you aren't using the default Firefox zoom level of 100%.
5. A refresh at this point might be necessary. Now, check the Firefox CPU usage. It should be around 100%.

I don't even know where to begin to hunt down this bug. I understand it's pretty specific, but because I browse zoomed in by a few percentages, and I use this filter, I'm concerned that other pages might be affected, as well.