Fine-tuning FireFox : Tips, tricks & tweaks!!!

Not open for further replies.


Wise Old Owl

Fine-tuning FireFox : Tips, tricks & tweaks:


Here I'll present the tips, tricks, tweaks for FireFox browser. You can apply these tricks on Firefox
running in any platform - Linux, Windows, Mac etc.,

Type about:config in the textfield where you type the URL like, etc.,
press Enter key.

You'll now see a "Filter" label, followed by a textfield. Whatever changes you want to make, you can type
the 'first-word.second-word' .For eg., type : network.http in the filter textfield, Firefox will
list all Preferences Name in Tabular format. Also note that now Firefox only lists those Preference names
that start with "network.http". So Firefox has filtered only those Preference names that start with

Let's move on to the next step. We need to change the values of the Preference names, so that we can tweak
FireFox as per our needs. There are three data types - 'String' , 'integer' and 'boolean'.

To change a String data type, select it , right-click, from the Popup dialog select 'Modify'. Now enter
the new String value , click on 'OK' button. For eg., Select network.http.version from the Table,
right-click select 'Modify'. Now a dialog box that appears "Enter string value". Type a new value you
want to set.Click on 'OK' to make the changes, or 'Cancel' to discard the changes you have made.
To modify an 'integer' value, select the row in the table like network.http.max-connections,
right-click , select 'Modify', now enter a new value you want to set. The last data-type is 'boolean'
A boolean data-type has only two states 'true' and 'false' (ie., On & Off). To change a boolean data type,
select the row from the table, right-click select 'Toggle' If the previous value is 'true' ,it changes
to 'false' after toggling and vice-versa.

Now let's get started. I'll be listing topic-wise on what changes to make in Firefox.

Load web pages faster: Speed-up Firefox:

"Broadband : 128kbps to 512 kbps"

network.http.max-connections -> 28

network.http.max-connections-per-server -> 16

network.http.max-persistent-connections-per-proxy -> 16

network.http.max-persistent-connections-per-server -> 16

network.http.pipelining -> true

network.http.pipelining.maxrequests -> 24

network.http.proxy.pipelining -> true

network.http.redirection-limit -> 8

network.http.request.max-start-delay -> 0

"Broadband : > 512 kbps"

network.http.max-connections -> 48

network.http.max-connections-per-server -> 24

network.http.max-persistent-connections-per-proxy -> 24

network.http.max-persistent-connections-per-server -> 24

network.http.pipelining -> true

network.http.pipelining.maxrequests -> 32

network.http.proxy.pipelining -> true

network.http.redirection-limit -> 8

network.http.request.max-start-delay -> 0

Reduce Memory Usage:

Firefox caches the data that it fetches from the webpages. There are two types of cache :
a) disk cache
b) memory cache

To view the cache type: about:cache

Disk cache speeds up loading of webpages since FireFox already has the Images, Flash & other
media types stored in the disk. So it will load only the new changes in the webpage & rest
it will load from the disk cache. So we'll leave disk-cache as it is.

As far as Memory Cache is concerned, it also speeds things up like faster loading of webpages,
but at the cost of memory!!! So if you browse lots of webpages with high-resolution Images & media,
Firefox slowly eats up memory & more memory until the O.S itself crawls to it's knees!!!
System becomes very slow, there is solution but to reboot the System or free memory using some
software. To reduce memory usage of Firefox, change the following Preference name value.

browser.cache.memory.enable -> false

Force Firefox to open the link in the same Window: -> 1

This also reduces memory usage considerably. If Firefox opens up new Window(forced to).It will
consume more memory & also it makes it difficult to switch between a pile of Windows!!!

Block Annoying Image Ads:

permissions.default.image -> 3

NOTE: If the Image Ad originates from a different website then it will be blocked.
If it is from the same website, it won't be blocked!!

You can also install Firefox extensions like 'Adblock', 'Adblock Plus', 'ImgLikeOpera', 'BlockSite' etc.,

Enable Auto-completion:

By enabling auto-completion ,you need not type the entire URL of the website.Just start typing a few
characters, Firefox will complete the rest!!!

browser.urlbar.autoFill -> true

Enable Spell-checking:

spellchecker.dictionary -> en_US

Increase Font-size:

If you viewing a webpage in a 17" monitor or higher then you'll notice that the fonts are so small.It's becomes
difficult to read webpages!! One way to overcome this is by : From the Firefox menu "View"-> "Text Size"->" Increase"
or "Ctrl++" But these changes won't persist!!! To overcome this, from the menu "Edit" -> "Preferences"

From the "FireFox Preferences" dialog, click on the tab 'Content' In 'Font & Colors' click on 'Advanced'

This opens up the "Fonts" dialog. Here next to label 'Monospace', set the 'Size' as '14' and also set the
'Mimimum font size' as '14'. Click on 'OK' button.

Get rid of annoying security dialogs:

Every time when you login to webpage like GMail, Yahoo, HotMail Banking sites & other Secure sites, Firefox displays
a annoying warning dialog "You are entering a secure site", "You are leaving a secure site" & so on.To get rid
of these irritants, do the following:

security.warn_entering_secure -> false

security.warn_entering_secure.show_once -> false

security.warn_entering_weak -> false

security.warn_entering_weak.show_once -> false

security.warn_leaving_secure -> false

security.warn_leaving_secure.show_once -> false

security.warn_submit_insecure -> false

security.warn_submit_insecure.show_once -> false

security.warn_viewing_mixed -> false

security.warn_viewing_mixed.show_once -> false

To view the Plugins installed:

Type about:plugins

NOTE: Apply these changes , you need to 'Quit' Firefox & restart it.

Happy Surfing!!!
Last edited:

Vishal Gupta

Microsoft MVP
Very nice attempt mate. Good work. :)
I have also posted a few tricks for Firefox at following link:

Mozilla Firefox Tweaks


Wise Old Owl
Thanks for your review @Vishal. We all know that @Vishal is a "Registry & System"
fine-tuning expert in Windows. Ok, I'll checkout your webpage.

Good post.
no offense meant but i knew most of the tricks :p

Still it will help the newbies.

Here my Contribution for a bug workaround:

In Firefox 3 Beta5(default broswer in Ubuntu)
BUG: excessive CPU usage and disk I/O
Problem: Browsing with Firefox 3.0b5 on Hardy leads to excessive CPU usage and disk I/O. The high CPU usage makes browsing very jerky - switching tabs takes more time than it should, pages appear frozen for a brief moment

1) remove FF3 beta & install FF2(Recommended, see below for exact procedure )
2) Delete urlclassifier3.sqlite file in your profile & restart FF3
3) Reduce Cache Size

Bugzilla@Mozilla – Bug 430530
Bug #215728 in firefox-3.0 (Ubuntu)

This sounds like a Linux only problem, still Windows users please confirm

[Howto] Remove Firefox 3 Beta5 in Ubuntu 8.04 & install Firefox 2(stable)

Open terminal(Applications->Accessories)
sudo apt-get remove firefox-3.0
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install firefox-2


Staff member
[Howto] Remove Firefox 3 Beta5 in Ubuntu 8.04 & install Firefox 2(stable)

Open terminal(Applications->Accessories)
sudo apt-get remove firefox-3.0
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install firefox-2

there is also an option in add/remove

Btw I kinda like FF3, so dont really want to uninstall it, will try to reduce the cache size


any good workaround ?

The Fix was out yesterday itself. 3rd may

so you want install the latest via cvs repos of mozilla


Wise Old Owl
Be brave & patient when using Products (in Beta state), If you want a stable version,
wait for some time until the annoying bugs are fixed or use the older version of
the product.


Wise Old Owl
For an Indepth, Complete, Comprehensive, detailed Analysis of about:config
options in FireFox , checkout this link :

Not open for further replies.
Top Bottom