Surprisingly few users know that Firefox is highly customizable – even without the help of add-ons. Here's how you can tailor the browser to fit your needs with 10 convenient about:config tweaks.

Anybody who is familiar with the “about:config” command for Firefox will likely have come to love the power it bestows upon users. It is the key to untold customization riches, the backstage pass to Firefox's HTML concert and your ticket into an unique and personalized browsing wonderland – if you know to to use it, that is. After all, though Firefox does a great job of allowing users to modify almost every inch of its interface with hundreds of parameters, it doesn't really explain any of them. Here's ten of the most useful about:config tweaks to cut through the confusion and give you an idea of what you can do with them. See also: How to delete persistent Firefox extensions and plug-ins

Note: All of the following parameters can be accessed in the same manner. Open up Firefox , type the line „about:config“ into the adress bar and hit enter. Confirm the warning by Firefox to access the list of configuration parameters for Firefox. You can search for the entry in question by entering its name (or a parts of its name) into the field called “Search:” at the top. Once you have found what you are looking for, double-click it to make changes (the boolean values “true” and “false” will just switch around). If you ever want to undo what you have possibly wrought, right-click the corresponding entry and select “reset”.

1. Auto-complete website URLs

Firefox offers the option to automatically fill in domain extensions if they are missing from the address bar. Great stuff, but unfortunately that only works for .com URLs. If you would like to change that setting to the British equivalent, so that an incomplete address like “www.pcadvisor” will automatically interpreted is “” and not as “”, look for the entry browserfixup.alternate.suffix and replace “.com” with “”.

2. Prevent Firefox from giving out your location to Google

Firefox continually transmits information about your current location to Google Location Services in order to interact with certain location-aware features of websites. This can be useful if you are looking for a nearby restaurant, a shop or service, as it typically saves you some time that would otherwise be spend navigating maps or entering your address. Note that Firefox will always ask you for permission before sharing this information with unfamiliar websites. However, also note that this ironically doesn't apply to Google itself, which Firefox supplies with this information quite freely.

To stop that, look for the entry geo.enabled and set it to “false”. To void any previous agreements to share your location with this service, its also a good idea to clear your browser cookies.

3. Customizing your tab start page

If you open a new tab in Firefox, you will be presented with nine website thumbnails chosen from your browsing history that are supposed to ease up navigation. Unfortunately, they are often little more than random assemblages of your past activities with no use whatsoever. And though customizing each of them manually can improve the experience, you might want to get a different tab start page altogether. To arrange for that, search for browser.newtab.url, double-click it and enter any website address to your liking.

4. Paste items from the clipboard with your middle mouse button

Instead of using the key combination Ctrl +V to paste items from the clipboard, you may also do so with your middle mouse button (by pressing your mouse wheel). While this neat little function is active by default under Linux, it is woefully missing in Windows. To remedy that, look for middlemouse.paste and set its value to “true”. In the rare case that it still doesn't work, check your mouse drivers to see whether or not the middle mouse button is active and has been properly configured.

Also take a look at: How to customize the browser toolbar in firefox

5. Activating pipelining

Firefox supports a method called “pipelining”, which could be described as multi-threaded surfing. In a nutshell, this means that instead of sending one request after another to a server, Firefox can send (and receive) multiple requests at the same time, potentially allowing websites to load much faster than normally possible. Keep in mind that not all pages support this method however and that loading times on smaller websites are often bottlenecked by a wide range of other factors, so that you might not notice any dramatic differences. Then again, giving pipelining a try shouldn't have any adverse effects either.

To enable pipelining, look for the entries network.http.pipelining, network.http.proxy.pipelining and network.http.pipelining.ssl and set them all to “true”.

6. Enable an universal zoom factor for Firefox

You can zoom in and out of websites by holding down Strg and pressing either + or -, or scrolling the mouse wheel. By default, Firefox (somewhat unreliably) remembers the zoom level for each website individually. If you don't want to bother adjusting every new site to your preferred zoom factor however, you can make this value consistent across the internet. To enable an universal zoom factor, search for the entry and set it to “false”.

7. Tab previews in the task bar

When Firefox is minimized, you can get a preview of the website that is currently loaded in it by hovering the cursor its symbol in the task bar. Obviously, this only works for the contents of a single tab. If you'd like to get an overview of all tabs that are open in Firefox, look for the entry browser.taskbar.previews.enable and switch it to “true”. Following this, you will get a whole row of previews right above the task bar corresponding the each individual tab. This can be quite useful, for example if you wish to jump right into the right website while Firefox is running in the background.

8. New tab for search results

The quick search bar, usually located right next to the address bar, is one of the most useful and convenient features of Firefox, as it allows users to skip directly to search results without needing to visit the website of the search engine first. For some reason, Firefox doesn't bother opening a new tab for these results by default though, thereby forcing users to open a new tab manually and ironically nullifying most of its benefits. To make Firefox open a new tab for the search results automatically, look for and set its value to “true”.

This might also be of interest: How to import your IE Favorites into

9. Free up memory while Firefox is minimized

It's no secret that Firefox can be fairly demanding of your memory – even if you are not even using the browser. If you have minimized Firefox, but other applications are being slowed down regardless, you can force Firefox to transfer parts of its session data from your RAM onto your hard drive, thus liberating some precious memory from its digital clutches. To do so, you will need to add a new entry to the about:config databank. Right-click anywhere into the list and select “New” followed by “Boolean”. Name the new entry config.trim_on_minimize and enter the value “true”.

10. Disable anti-virus scanning for downloads

Firefox automatically requests all downloads to be scanned by any installed anti-virus software upon completion. While this feature certainly means well, it tends to unnecessarily suspend and freeze files for dozens of seconds - even if they were downloaded from trusted sources and are perfectly harmless. Here's how you can disable that feature and save some time: Look for the entry and set it to “false”.Obviously, make sure to be careful and have up-to-date security software monitoring your system at all times, as disabling this function comes at your own risk.