Firefox's extendibility is one of its great advantages, and there are thousands of plug-ins to choose from.

But having so much choice can be confusing, and it's often hard to tell which add-ons are worth installing and which are best left alone. So look no further - here's our 12 essential Firefox extensions. Download them now!

1. Copy plain text
Ever copied something from the web into a document only to have it ruined because the formatting is also copied? Fix this by getting Copy as Plain Text. Once it's installed, highlight some text, right-click on it and choose 'Copy as plain text' to do just that.

2. Get TinyURLs
This add-on lets you create shortened URLs without having to go to a separate web page. Install TinyURL Creator 1.0.5. Now browse to the site you want to share, right-click anywhere and choose 'Create TinyURL for this page'. The result is automatically copied to the clipboard.

3. Use hyperwords
For the Swiss army knife of text add-ons, get Hyperwords. Once installed, it provides you with a dizzying array of options for highlighted text through its right-click menu. Choose 'Search' and then select from Google, the current site or a range of news sites and social-networking services for immediate search results. You can also look up the selection in a range of reference sites, including Wikipedia and the Urban Dictionary. There are also options to translate the text or share it with others.

4. Resurrect pages
When a website that you need goes down, you can hunt through each of the various caching services manually to find a snapshot of it, but this can be time-consuming. The Resurrect Pages extension does the hard work for you, replacing the standard 'page cannot be displayed' message with one that includes links to web cache services. Use these to quickly see if a service has a cached version of the page you want.

5. Avoid typos
It's easy to make a mistake when typing in a web address. URL Fixer 1.5 anticipates common mistakes and sets them right so that you're not left with a broken link. It won't catch every slip, but it will help reduce your irritation levels a little.

6. Block ads
Adverts can be a big irritation. The AdBlock Plus extension enables you to block adverts that you don't want to see while allowing you to permit them for other sites. You can also set it up to block content from a number of different subscription services, and opt to turn off its filter for sites that you approve of.

7. Block script
Some sites execute code without your explicit permission. In a few cases, like that of the Twitter worm Mikeyy, this can be abused. No Script blocks all third-party scripts – including JavaScript, Java and Flash objects – until you give your permission for them to run. You can also identify sites as trusted so that you're not constantly vetting scripts on familiar pages.

Noscript

8. Pretend to be IE
Some webmasters are wise to the fact that Firefox users can block ads and scripts with plug-ins, so they prevent access to their sites for people using Firefox. User Agent Switcher disguises your browser as Internet Explorer to get round this restriction. The utility adds a sub-menu to the Tools menu that enables you to select the browser and OS that you want to display to sites.

9. Run IE in Firefox
Some sites need Internet Explorer to render properly. Rather than close Firefox, try IE Tab. Right-click and choose 'Open Page in IE tab' to open a new tab that emulates Internet Explorer.

10. Add Google Bookmarks
Use the GMarks extension to integrate your Google Bookmarks with Firefox. Log into your Google account to replace the existing Bookmarks menu and Bookmarks Toolbar folder with GMarks. This is a handy way to keep all of your bookmarks in one place.

11. Add bookmarks from IE
Another bookmark synchronising add-on is Xmarks that has evolved from an earlier extension known as Foxmarks. You can use it to synchronise your bookmarks with Internet Explorer and Safari, meaning that you'll have quick access to your favourite pages no matter which browser you're using. It also provides site suggestions and community feedback.

12. Check site security
McAfee's Site Advisor add-on provides a service that's focused on making sure that you're safe online. When you run a Google search, each result is either rated as 'safe' or has any potential problems flagged. Hover over the Site Advisor icon next to the result to find out more.

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First published in PC Plus Issue 284

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