Well I&#x27;m sure profiles are a part of it.  It got bad enough that I completely removed all profile and plugin data, and clean reinstalled.  Firefox remains the worst performing browser I have on this system by very large measure.<p>Five amazon tabs are enough to basically grind it to a halt.  Chrome, IE, Opera and Palemoon (a fork of an older firefox) don&#x27;t do that.<p>So I&#x27;ve reached a point where I can&#x27;t do much more to make it usable without a debugger.  I&#x27;ve no doubt others are fine, or find Chrome the slow one.  If everyone had the issues I currently have it&#x27;d be the single highest priority bugfix in the project.<p>I&#x27;d maybe migrate to palemoon but I don&#x27;t trust it on a security front.