Firefox 27.0.1 Slowdown

I’m noticing that on FF 27 & 27.0.1, certain sites that use JavaScript will eventually become slow to navigate, along with any other site browsed. The more I navigate certain sites, the slower FF gets as a whole. This means opening up new tabs lags, all sites eventually lag, and clearing the cache does nothing. Restarting the browser fixes the problem. Is anyone else experiencing this?