Perhaps related to this FF bug: https://bugzilla.mozilla.org/show_bug.cgi?id=759342
I've had a few other sites trigger my 100% cpu FF issue, but it's almost guaranteed to happen within viewing 4 pages of forums on mtbr. Because it's not specific to the whole site, it might be code within one or some of the ads.
I've just switched browsers again (Chrome/SW Iron now that the kernel panic has been hopefully patched).
So more of an FYI or see if others are having issues.
Mtbr's 2016 Winter Biking GearReviews and Roundups
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