So I went to google and found 5 easy-to-do tweak with remarkable results! Remarkable, because you truly can see the difference between a standard and a tweaked Firefox. One might wonder why such tweaks are not standard options..

Type “about:config” into the address bar and hit return. Look for the following entries:

1. "network.http.pipelining" and set value to true
2. "network.http.proxy.pipelining" and set value to true
3. "network.http.pipelining.maxrequests" and set value to 30-40
4. "nglayout.initialpaint.delay" and set value to 0
5. "config.trim_on_minimize" and set value to true

If you don't have them, create them:

1. Right click -> new -> boolean -> type in "network.http.pipelining" -> set value to true
2. Right click -> new -> boolean -> type in "network.http.proxy.pipelining" -> set value to true
3. Right click -> new -> boolean -> type in "config.trim_on_minimize" -> set value to true
4. Right click -> new -> integer -> type in "network.http.pipelining.maxrequests" -> set value to 30 (default is 1)
5. Right click -> new -> integer -> type in "nglayout.initialpaint.delay" -> set value to 0

Now the explanation as to what does what:

network.http.pipelining and network.http.proxy.pipelining:

It enables pipe-lining, which means the browser normally sends 1 request at a time, with pipeline enabled it will send the amount of request you set in "network.http.pipelining.maxrequests"!

network.http.pipelining.maxrequests:

Like I said Firefox usually sends 1 request at any time. By setting a different value than 1, you force Firefox to send more requests thus enabling it to load faster, because he gets more responses at any time.

config.trim_on_minimize:

Each time you minimize your Firefox it will clear the RAM. Firefox is infamous of wasting RAM for Pages you don't need so you can go "back" to them.

nglayout.initialpaint.delay:

If this value doesn't exist or isn't set Firefox waits 250 milliseconds, or 0.25 of a second then starts rendering the requested page(s). People report that setting it to 0, ergo forcing Firefox to begin rendering immediately causes almost all pages to show up faster.

Addendum:

If you are one of the lazy lot, and don't want to manually tweak your Firefox, here's a great Extension with virtually the same effect

Fasterfox: https://addons.mozilla.org/en-US/firefox/addon/1269

Enjoy your new, faster Firefox!

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