How To Speed Up Firefox 9 Tweaking Guide

Skill Level: Medium

Firefox 9 has just been released – I already discussed the new features in it but what about tweaking Firefox 9 to make it even quicker?

There are several guides around the internet but many are years old or just plain wrong. In particular, Firefox 9 has made changes ‘under the hood’ which make some previous tweaks for earlier versions of Firefox redundant or even undesirable.

Initial Steps

Before tweaking, check for any add-ons that you no longer use or could do without – the more you have installed, the slower and less stable Firefox will become:

• In the Firefox menu bar click Tools then Add-ons to open the Add-ons Manager. Now click on Extensions and if you no longer need an extension then remove it or at least disable it. Restart Firefox when you have finished.
  

Likewise, disable any plugins you do not use:

• In the Firefox menu bar click Tools then Add-ons to open the Add-ons Manager. Now click on Plugins and if you do not need a plugin then disable it. Restart Firefox when you have finished.

The only plugin enabled on my system is Shockwave Flash which is essential for streaming video e.g. YouTube – amongst my disabled plugins are Microsoft DRM, Quicktime, VLC, Windows Media Player, Google Update etc which I have never found a need for – but if you do find a site that needs a specific plugin to work then just re-enable it.

Backing Up

The following tweaks are done by changing or adding values in the Firefox configuration page known as about:config. You should make a note of the ‘before’ and ‘after’ values of each tweak and (highly recommended!) backup the Firefox preferences file that contains all the configuration options in case you want to revert back to your original settings:

The configuration file is called prefs.js and can be found in the following place in your operating system drive (usually C: drive):

\Documents and Settings\<username>\Application Data\Mozilla\Firefox\Profiles\<profile ID>.default\ inWindows XP or

\Users\<username>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile ID>.default\ in Vista and Windows 7.

You may need to show hidden files to view the folder. Copy the prefs.js file to another location on your hard drive whilst Firefox is closed.

Tweaking Firefox 9

Open Firefox and type about:config in the address bar and press Enter. Click the “I’ll be careful I Promise” warning button to reveal a long list of preferences used in Firefox.

• To change a preference – if it is an integer (number) or a string (text), double click on the preference name and you will be prompted for the new value. If it is a Boolean (true or false) value, double click the entry to switch from true to false or vice versa – double clicking it again will revert it to its original value.

• To add a preference (if the preference name is not already listed in your about:config page) right click on an empty space in the about:config window and choose New followed by String, Integer or Boolean depending whether the value of the preference is text (String), a number (Integer) or true/false (Boolean).

Tip: You can scroll down the list of preferences but the quickest way to find the right one is to type part of the preference name into the Filter bar at the top of the config page – this automatically reduces the list to show only those preferences that include the text you typed.

Changing Preferences

Change or add the following preferences to the new values shown. If the preference is already set to this value then skip it and move on the next. If the preference does not exist then you need to add it:

browser.display.show_image_placeholders: false

Stops the display of placeholders while images are loading to speed up the page. Default is True

browser.tabs.animate: false

Disables all tab animation features (e.g. when you click the ‘New Tab’ (+) button) to make the tab interface feel quicker. Default is True

network.prefetch-next: true

This allows Firefox to automatically prefetch (load) the contents of pages linked to by the page you are viewing e.g. this site uses prefetch to load the TechLogon homepage in the background, making it quicker for you to view next if you want to For pure internet speed, keep this setting at the Default which is True.

network.http.max-persistent-connections-per-server: 8

Increases the maximum number of persistent connections per server which can help speed up loading of multimedia rich sites. Default is 6

network.http.pipelining: true

Can send multiple requests to a server together in order to speed up loading of webpages. This is not supported by ALL servers – some servers may even behave incorrectly if they receive pipelined requests. Default is False

network.http.pipelining.maxrequests: 8

Sets a maximum number of multiple requests that can be pipelined to prevent overloading the server. Higher values will cause a delay before the first request completes but will make the last request complete sooner. Higher values will also cause more of a delay if a connection fails. The maximum value is 8. Default is 4

network.dns.disableIPv6: true

Disables IPv6 DNS lookups to prevent a significant delay with poorly configured IPv6 servers. Default is False

Optional: if you want Google searches in the address bar to search by name and go straight to the right website (e.g. NewYorkTimes would go straight to the nytimes.com website) rather than just perform a standard Google search, add the text below to the following value:

keyword.url: http://www.google.com/search?ie=UTF-8&oe=UTF-8&sourceid=navclient&gfns=1&q=

(this is for google.com – you may want to change it to your own country version e.g. for UK just replace the google.com bit with google.co.uk)

Now close Firefox and re-open it to apply all the tweaks – you should find Firefox is quicker and more responsive

Personalizing The Tweaks

The above tweaks for Firefox 9 improve speed and responsiveness in my own tests – but your mileage may vary depending on your exact network configuration, sites visited and other software installed. One of the best things about Firefox is the variety of add-ons available – it is also one of the worst as it means there is an endless variety of possible Firefox 9 configurations…

In particular the five ‘network.’ preferences may not be a ‘one size fits all’ solution for you – you may need to experiment to achieve the best settings for your particular implementation of Firefox e.g. by changing them one at a time to different values or back to the default setting. I provided the Firefox 9 default settings above in case you wish to revert to them.

Still Having Speed Or Crashing Problems?

If you have always let Firefox upgrade itself over the years (e.g. from version 3 or 4 onwards) or you have installed loads of add-ons and now find Firefox slow or unresponsive, you should seriously consider making a fresh start with a brand new Firefox installation – see reinstalling Firefox from scratch to fix speed and stability issues.

Related posts:

1. How To Speed Up Firefox 8 Tweaking Guide
2. How To Speed Up Firefox 4 Tweaking Guide
3. How To Speed Up Firefox 6 Tweaking Guide
4. How To Speed Up Firefox 7 Tweaking Guide
5. How To Speed Up Firefox 5 Tweaking Guide