about:config gives you a visual interface where you can find the name of a preference and see or change its current value. You can also add new or hidden preferences via this interface. To open the about:config page, all you have to do is type about:config in the location bar (this is where you would normally type a web address) and press Enter.
1. Adjust the Smart Location Bar’s Number of Suggestions
In Firefox, when you start typing in the location bar, a drop-down list of suggestion URLs will be shown. That is your History of Previously Opened Websites. Maximum of 12 Links it shows.
In Firefox, when you start typing in the location bar, a drop-down list of suggestion URLs will be shown. That is your History of Previously Opened Websites. Maximum of 12 Links it shows.
- Search in Filter Bar : browser.urlbar.maxRichResults
- Default : 12
- Modified 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 automatically saves your session every 10 secs so that whenever it crashes, it can restore all your tabs.
- Search in Filter Bar : browser.sessionstore.enabled
- Default : True
- Modified value : False if you want to disable the session restore function.
3. Enable Advanced Color Profile Support
Firefox 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.
- Search in Filter Bar : gfx.color_management.enabled
- Default : False
- Modified value : True (if you want to activate the color profile support feature).
4. Disable Antivirus Scanning
This is mainly for Windows users. By default, Firefox 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.
- Search in Filter Bar : browser.download.manager.scanWhenDone
- Default : True
- Modified value : False (if you want to disable it).
5. Show/Disable Close button on Tabs
Some 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.
- Search in Filter Bar : browser.tabs.closeButtons
- Default : 1
- Modified 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.
6. Lower The Physical Memory Used When Minimized
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_minimize
- Enter the values : True
7. Extend Scripts Execution Time
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.
- Search in Filter Bar : dom.max_script_run_time
- Default : 10 (in secs)
- Modified value : 20, or any values greater than 10.
When a page is loaded, Firefox will cache it into the hard disk so that it doesn’t need to be download again for re-displaying. The bigger the storage size you cater for Firefox, the more pages it can cache.
- Search in Filter Bar : browser.cache.disk.capacity
- Default : 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.
9. Speed up your Firefox
Several tweaks required for this. You Have to Filter Many Preferences.
- Search in Filter Bar : network.http.pipelining
- Default : False
- Modified value : True
- Search in Filter Bar : network.http.proxy.pipelining
- Default : False
- Modified value : True
- Search in Filter Bar : network.http.pipelining.maxrequests
- Default : 4
- Modified value : any value higher than 4, but not more than 8.
- Search in Filter Bar : network.http.max-connections
- Default : 30
- Modified value : 96
- Search in Filter Bar : network.http.max-connections-per-server
- Default : 15
- Modified value : 32
10. Autofill Address in URL Bar
Other than the smart location feature, you can also get your URL bar to auto-fill the address as you type the URL.
- Search in Filter Bar : browser.urlbar.autofill
- Default : True
- Modified value : False (enable same zoom preferences for every sites).
11. Setting your zoom limit
- Search in Filter Bar : zoom.maxPercent
- Default : 300 (percent)
- Modified value : any value higher than 300.
- Search in Filter Bar : zoom.minPercent
- Default : 30 (percent)
- value : any value
12. Auto Export Firefox bookmarks to bookmarks.html
Firefox backup the bookmarks file in places.sqlite rather than the usualbookmarks.html. Since bookmarks.html allows us to export and sync our bookmarks with other browser, it will be very useful if Firefox 3 backup the bookmark to the bookmarks.html as well.
- Search in Filter Bar : browser.bookmarks.autoExportHTML
- Default : False
- Modified value : True (auto export bookmarks file to bookmarks.html)
13. Disable Extension Compatibility Checks
This 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.
14. 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.
- Search in Filter Bar : security.dialog_enable_delay
- Default : 2000 (in msec)
- Modified value : 0 – start installation immediately
15. View Source in Your Favorite Editor
- Search in Filter Bar : view_source.editor.external
- Default : False
- Modified value : True ( enable view source using external text editor).
- Search in Filter Bar : view_source.editor.path
- Default : blank
- Modified value : insert the file path to your editor here.
16. Open Search Results In A New Tab
- Search in Filter Bar : browser.search.openintab
- Default : False
- Modified value : True