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Firefox Tweaks
Good list, including some that I'm not sure are worth it.
Most important (IMHO):
{{{network.http.pipelining true}}}
{{{network.http.proxy.pipelining true}}}
{{{network.http.pipelining.maxrequests 4}}} - Make sure this is a small number, as it is bad netiquette to make it big (> 8 or so?) and it may get you banned from some sites.
{{{nglayout.initialpaint.delay 0}}} - Or a small number (in ms, so 1000 = 1 sec) to avoid flashing behavior. Must be added as a new integer value.
{{{ui.submenuDelay 0}}}
{{{network.dns.disableIPv6}}} - Hardly necessary at this point in time, and apparently can have a very detrimental effect on Firefox's performance.