Make older add-ons work with Firefox 3.0

Fortunately, there is a solution that will "fix" all of your extensions at once

If you're like me, you've been playing around with the beta releases of Firefox 3.0. The new version of the open source browser is better-looking, uses less memory, and feels snappier all around. There's just one problem: Every time they release a new beta version, some of your extensions and add-ons are bound to stop working. With the release of Firefox 3.0rc1, almost none of them work.

Fortunately, there is a solution that will "fix" all of your extensions at once. But I caution you, it's not for the weak-hearted. The fix doesn't take longer than a few seconds, but when it comes to troubleshooting your browser afterward, you'll be on your own.

I can't repeat this enough. DO NOT TRY THIS unless you are comfortable editing the advanced preferences of your browser. And don't do anything until you've read through this entire post. Don't say I didn't warn you.

In my experience, extensions that worked with Firefox 3.0b5 will generally be stable with 3.0rc1. It is possible, however, that some of them will cause the new version of the browser to crash. It might even crash on startup -- which means, obviously, that you won't easily be able to undo the fix I'm about to describe.

The key to the fix is to prevent Firefox from checking its version number before it tries to load extensions. To do this, you will need to set a new preference value. Point your browser at the URL "about:config", then right-click on the preferences list to bring up the contextual menu. You should see an option that says "New." Select that, and choose "Boolean." When it asks you for the preference name, type "extensions.checkCompatibility" (without the quotes). You have to enter the name exactly. For the value, choose "false."

Now restart Firefox. When the browser comes back up, it should give you a warning that version checking is disabled. You can double-check under "Tools:Add-Ons" to make sure everything is activated once again.

If the worst case happens and the browser won't start after you add the new preference, you'll need to remove it by hand. Locate the file "prefs.js" within your Firefox profile directory and edit it with any text file editor to delete the line with the preference you just created. (If you're not comfortable doing that, then as I've said, this fix is probably not for you.)

Also, you'll want to remember to delete the preference once the final version of Firefox 3.0 is released, or else you'll never be certain that your installation is stable.

Good luck. As I've said before, I can't troubleshoot any individual Firefox installations. But hopefully this will help you keep your most-beloved add-ons running until their maintainers update them for the final Firefox 3.0.

Join the newsletter!

Error: Please check your email address.
Rocket to Success - Your 10 Tips for Smarter ERP System Selection
Keep up with the latest tech news, reviews and previews by subscribing to the Good Gear Guide newsletter.

Neil McAllister

PC World
Show Comments

Cool Tech

SanDisk MicroSDXC™ for Nintendo® Switch™

Learn more >

Breitling Superocean Heritage Chronographe 44

Learn more >

Toys for Boys

Family Friendly

Panasonic 4K UHD Blu-Ray Player and Full HD Recorder with Netflix - UBT1GL-K

Learn more >

Stocking Stuffer

Razer DeathAdder Expert Ergonomic Gaming Mouse

Learn more >

Christmas Gift Guide

Click for more ›

Most Popular Reviews

Latest Articles

Resources

PCW Evaluation Team

Edwina Hargreaves

WD My Cloud Home

I would recommend this device for families and small businesses who want one safe place to store all their important digital content and a way to easily share it with friends, family, business partners, or customers.

Walid Mikhael

Brother QL-820NWB Professional Label Printer

It’s easy to set up, it’s compact and quiet when printing and to top if off, the print quality is excellent. This is hands down the best printer I’ve used for printing labels.

Ben Ramsden

Sharp PN-40TC1 Huddle Board

Brainstorming, innovation, problem solving, and negotiation have all become much more productive and valuable if people can easily collaborate in real time with minimal friction.

Sarah Ieroianni

Brother QL-820NWB Professional Label Printer

The print quality also does not disappoint, it’s clear, bold, doesn’t smudge and the text is perfectly sized.

Ratchada Dunn

Sharp PN-40TC1 Huddle Board

The Huddle Board’s built in program; Sharp Touch Viewing software allows us to easily manipulate and edit our documents (jpegs and PDFs) all at the same time on the dashboard.

George Khoury

Sharp PN-40TC1 Huddle Board

The biggest perks for me would be that it comes with easy to use and comprehensive programs that make the collaboration process a whole lot more intuitive and organic

Featured Content

Latest Jobs

Don’t have an account? Sign up here

Don't have an account? Sign up now

Forgot password?