How to Speed Up Firefox:
Method 1:  (By changing Developer settings)
Accessing your  about:config  page
In your Firefox, type  
about:config  in the address bar.
You will be shown a warning page. Click the “
I’ll be careful, I promise!” button to proceed.
On the main page, you will see a long list of configuration entries. Enter the name of the key you want to update in the “
Filter” field. The list will narrow to only the entries that match your keyword as you type.
To modify the value, simply double click on the entry value field and update the entry. That’s all!
Isn’t that simple? Now, let’s get to the tweaking.
1) Adjust the Smart Location Bar’s Number of SuggestionsIn  Firefox 3, when you start typing in the location bar, a drop-down list  of suggestion URLs will be shown. If you want it to show more than 12  suggestions (12 is the default), you can adjust the 
browser.urlbar.maxRichResults keys and get it to show the number you want.
Config name:  
browser.urlbar.maxRichResults
 Default: 
12Modified value: 
Set to your desired number of suggestion. If you want to disable it all together, set it to -1
2) Disable the session restore function Firefox  3 automatically saves your session every 10 secs so that whenever it  crashes, it can restore all your tabs. While this is a useful feature,  some of you might find it irritating. To disable this function, toggle  the value of 
browser.sessionstore.enabled to 
FalseConfig name:  
browser.sessionstore.enabledDefault:  
TrueModified value:  
False if you want to disable the session restore function 
3) Adjust the Session Restore Saving FrequencySame  as above, if you decided to keep the session restore feature on, but  want to reduce the session saving frequency, change the value of 
browser.sessionstore.interval so that Firefox will save the session at a longer interval.
Config name:  
browser.sessionstore.interval
 Default:  
10000 (in msecs, equivalent to 10secs)Modified value: 
Set it to your desired value. 1000 means 1 sec and 60000 means 1 minute. 
4) Enable Advanced Color Profile SupportFirefox  has this advanced color profile features that display higher image  quality. It is not enabled by default as it has a negative effect on the  performance of the browser. If you are concern with the image quality  rather than the performance, you can activated it via the 
gfx.color_management.enabled setting
Config name:  
gfx.color_management.enabled
 Default:  
FalseModified value:  
True (if you want to activate the color profile support feature)
5) Disable Antivirus ScanningThis  is mainly for Windows users. By default, Firefox 3 automatically scan  the downloaded file with the default anti-virus application to make sure  it is free of virus. If you download a big file, it could take a long  time for the whole scanning process to complete. To increase the  performance of the browser, you might want to consider disabling the  anti-virus scanning via the 
browser.download.manager.scanWhenDone key.
Config name:  
browser.download.manager.scanWhenDoneDefault:  
TrueModified value:  
False (if you want to disable it)
6) Configuring The Scrolling TabsWhen  you opened many tabs, Firefox will not keep on reducing the tab width.  Instead, it shows a scrolling bar so that the min width (100px) is  conserved and you can scroll to find your tabs. If you are those who  don’t like the scrolling tab function and prefer Firefox to show all the  tabs, regardless how small it is, you can set the value of 
browser.tabs.tabMinWidth to 0 to disable it. Similarly, if you want Firefox to display more tabs  before showing the scrolling button, you can reduce the default value  to a lower value, say 75 pixels.
Config name:  
browser.tabs.tabMinWidth
 Default:  
100Modified value:  
0  (if you want to disable the scrolling functions, other values to set the min width value)
7) Show/Disable Close button on TabsSome people love to see the 
Close (the red X) button on every tabs, but some hate it. Whatever is it, you can configure it to your preferences via the 
browser.tabs.closeButtons setting.
Config name:  
browser.tabs.closeButtons
 Default:  
1Modified values:
- 0 – display a close button on the active tab only 
 - 1- display close buttons on all tabs 
 - 2- don’t display any close buttons
 - 3- display a single close button at the end of the tab strip 
 
8) Extend Scripts Execution TimeIn  Firefox 3, a script is only given 10 seconds to respond, after which it  will issue a unresponsive script warning. If you are hooked on a slow  network connection, you might want to increase the script execution time  via 
dom.max_script_run_time to cut down on the frequency of the no script warning.
Config name:  
dom.max_script_run_timeDefault:
 10 (in secs)Modified value:  
20, or any values greater than 10
9) Handling JavaScript Popups When  you come across a site that executes a javascript open new window  function, and if the popup window is without all the usual window  features, i.e. 
back/forward/reload buttons, status bar etc,  Firefox will automatically treat it as a popup and will not open it as a  new tab. However, if you find this to be a nuisance and wanted to open  all new windows in a new tabs, you can specify it via the 
browser.link.open_newwindow.restriction setting.
Config name:  
browser.link.open_newwindow.restrictionDefault:  
2 – Open all JavaScript windows the same way as you have Firefox handle  new windows unless the JavaScript call specifies how to display the  window
 Modified values:
- 0 – open all links as how you have Firefox handle new windows
 - 1 – do not open any new windows
 - 2- open all links as how you have Firefox handle new windows unless the Javascript specify how to display the window 
 
10) Enable Spell Checking In All Text Fields The  default spell checking function only checks for multi-line text boxes.  You can get it to spell-check for single line text box as well.
Config name:  
layout.spellcheckDefaultDefault:  
1 (spell checker for multi-lines text boxes only)Modified values:
- 0 – disable the spell checker
 - 2 – enable the spell checker for all text boxes 
 
11) Open Search Box Results In New TabWhen  you search using the search box at the top right hand corner of the  browser, it will display the search results in the current tab. If you  don’t want the search to interfere with your current tab, you can tweak  the 
browser.search.openintab to make it open in a new tab.
Config Name:  
browser.search.openintab
 Default:  
FalseModified value:  
True (open search box results in new tab)
12) Lower The Physical Memory Used When MinimizedThis  tweak is mainly for Windows users. When you minimize Firefox, it will  send Firefox to your virtual memory and free up your physical memory for  other programs to use. Firefox will reduce its physical memory usage,  when minimized, to approximately 10MB (give or take some) and when you  maximize Firefox it will take back the memory that it needs.
The preference name does not exist and needs to be created.
Right click on the background and select  
New ->Boolean.Enter the name when prompted:  
config.trim_on_minimizeEnter the values:  
True
13) Speed up your FirefoxSeveral tweaks required for this
Config name:  
network.http.pipeliningDefault:  
FalseModified value:  
TrueConfig name:  
network.http.proxy.pipeliningDefault:  
FalseModified value:  
TrueConfig name:  
network.http.pipelining.maxrequests
 Default:  
4Modified value: 
any value higher than 4, but not more than 8 Config name:  
network.http.max-connectionsDefault:  
30Modified value:  
96Config name:  
network.http.max-connections-per-serverDefault:  
15Modified value:  
32
14) Increase/Decrease the Amount of Disk CacheWhen  a page is loaded, Firefox will cache it into the hard disk so that it  doesn’t need to be download again for redisplaying. The bigger the  storage size you cater for Firefox, the more pages it can cache.
Before you increase the disk cache size, make sure that 
browser.cache.disk.enabled browser.cache.disk.enable is set to 
True.
Config name:  
browser.cache.disk.capacityDefault:  
50000 (in KB)Modified value:
- 0 – disable disk caching 
 - any value lower than 50000 reduces the disk cache 
 - any value higher than 50000 increases the disk cache.
 
15) Select all text when click on the URL barIn  Windows and Mac, Firefox highlights all text when you click on the URL  bar. In Linux, it does not select all the text. Instead, it places the  cursor at the insertion point. Regardless which platform you are using,  you can now tweak it to either 
select all or 
place cursor at insertion point.
Config name: 
browser.urlbar.clickSelectsAllModified value:
- False – place cursor at insertion point
 - True – select all text on click
 
16) Autofill Address in URL BarOther than the smart location feature, you can also get your URL bar to autofill the address as you type the URL.
Config name: 
browser.urlbar.autofillDefault: 
FalseModified value: 
True (Have Firefox autofill the address as you type in the URL bar)
17) Same Zoom Level For Every SiteFirefox  remembers your zoom preference for each site and set it to your  preferences whenever you load the page. If you want the zoom level to be  consistent from site to site, you can toggle the value of 
browser.zoom.siteSpecific from 
True to 
False.
Config name:  
browser.zoom.siteSpecificDefault: 
TrueModified value: 
False (enable same zoom preferences for every sites) 
18) Setting your zoom limitIf  you find that the max/min zoom level is still not sufficient for your  viewing, you can change the zoom limit to suit your viewing habits.
Config name:  
zoom.maxPercentDefault: 
300 (percent)Modified value: 
any value higher than 300Config name: 
zoom.minPercentDefault:
 30 (percent)
 value: 
any value 
19) Configure Your Backspace ButtonIn Firefox, you can set your backspace to better use by getting it to either go back to the 
previous page or act as 
page up function.
Config name: 
browser.backspace_actionDefault: 
2 (does nothing)Modified value:
- 0 – go back previous page
 - 1- page up 
 
20) Increase Offline CacheIf  you do not have access to Internet most of the time, you might want to  increase the offline cache so that you can continue to work offline. By  default, Firefox 3 caches 500MB of data from supported offline Web apps.  You can change that value to whatever amount of your choice.
Config name:  
browser.cache.offline.capacityDefault: 
512000 (in KB)Modified value: 
any value higher than 512000 will increase the cache value
21) Auto Export Firefox 3 bookmarks to bookmarks.htmlUnlike the previous version, Firefox 3 backup the bookmarks file in 
places.sqlite rather than the usual 
bookmarks.html. Since 
bookmarks.html allows us to export and sync our bookmarks with other browser, it will  be very useful if Firefox 3 can backup the bookmark to the 
bookmarks.html as well.
Config name: 
browser.bookmarks.autoExportHTMLDefault: 
FalseModified value: 
True (auto export bookmarks file to bookmarks.html)
22) Disable Extension Compatibility ChecksThis  is useful if you want to use an extension that is not supported by your  version of Firefox badly. It is not recommended, but you can still do  it at your own risk.
Right click and select 
New->Boolean. 
Enter 
extensions.checkCompatibility in the field.
Enter 
False in the next field.
Right click again and select 
New->Boolean. 
Enter 
extensions.checkUpdateSecurity into the field and 
enter 
False into the next field.
23) Disable Delay Time When Installing Add-on Everytime  you wanted to install a Firefox add-on, you will have to wait for  several secs before the actual installation starts. If you are tired of  waiting, you can turn the function 
security.dialog_enable_delay off so that the installation will start immediately upon clicking.
Config name:  
security.dialog_enable_delayDefault: 
2000 (in msec)Modified value:
- 0 – start installation immediately 
 - any other value (in msec)
 
24) View Source in Your Favorite Editor This is very useful for developers who are always using the 
‘view source‘ function. This tweak allows you to view the source code in an external editor.
There are two configuration need to be made:
Config name:  
view_source.editor.externalDefault:
 FalseModified value: 
True ( enable view source using external text editor)Config name:  
view_source.editor.pathDefault: 
blankModified value: 
insert the file path to your editor here.
25) Increasing ‘Save Link As‘  timeout value When you right click and select the 
‘Save Link As…‘,  the browser will request the content disposition header from the URL so  as to determine the filename. If the URL did not deliver the header  within 1 sec, Firefox will issue a timeout value. This could happen very  frequently in a slow network connection environment. To prevent this  issue from happening frequently, you can increase the timeout value so  as to reduce the possibility of a timeout.
Config name:  
Browser.download.saveLinkAsFilenameTimeoutDefault: 
1000 (1 sec)Modified value: 
any value higher than 1000 (value is in msec) 
26) Animate Fullscreen Toolbar Collapse modeIn  Firefox’s fullscreen mode, toolbars and the tab strip are hidden at the  top of the screen and only shown on mouseover. To draw attention to  this, there is an animation of the toolbar sliding upwards and  off-screen when fullscreen mode is toggled on. For performance issue,  the animation of the collapse of the toolbar only appear for the first  time. For some reason that you may love/hate the animation, you can  adjust 
Browser.fullscreen.animateUp to switch it on/off for every collapse.
Config name:  
Browser.fullscreen.animateUpDefault: 
1 (animate the toolbar collapse only the first time)Modified value:
- 0 -disable the animation 
 - 2- enable the animation for every collapse 
 
27) Autohide Toolbar in Fullscreen mode In  fullscreen mode, the toolbar is set to autohide and appear upon  mouseover. If you have a need to view the toolbar at all time, you can  toggle the value of 
browser.fullscreen.autohide to 
False to always show the toolbar.
Config name:  
browser.fullscreen.autohideDefault: 
True (always autohide)Modified value: 
False (always show the toolbar)
28) Increase Add-On search resultIf you go to 
Tools->Add-ons->Get Add-ons and perform a search there, Firefox will only fetch and display 5  matching results. If you want Firefox to show more than 5 results (say  10), you can adjust 
extensions.getAddons.maxResults to get it to display more results.
Config name:  
extensions.getAddons.maxResultsDefault: 
5Modified value: 
any value more than 5
Restart Firefox & Enjoy Speed....
Method 2:  Use Firefox extensions for speeding it up.
 There are a lot of Firefox extensions are available for speeding up Firefox, some of them are below: 
1. SpeedyFox: An extension to speed up your browsing. Download the extension from  
Here 
2. BetterFox: Another official extension by Mozilla  “To make browsing experience 15 times faster” as it claims. Download  this speedup extension  
Here
OR
 Simple Trick To Speed Up FireFox
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