Which Firefox versions are supported?

For the best security and online experience we recommend that you run the latest version of Firefox that your system can support. Below are all the versions of Firefox that we support.

Firefox 6 and 7

Snow Leopard and Lion

Our extension is compatible with Firefox 6 or 7 on Snow Leopard and Lion. You can grab our extension for the latest version of Firefox from our browser extension download page.

Firefox 5

Snow Leopard and Lion

The Firefox 5 extension is available starting in 1Password 3.6 which is available to Mac OS X Snow Leopard and Lion users by opening 1Password and selecting 1Password > Check for Updates from the menu-bar.

If you have any troubles getting 1Password to appear, please see the Troubleshooting section below.

Leopard

Firefox 5 is supported in OS X 10.5 (Leopard) in 1Password 3.5 and is available to download here

Firefox 4 on Mac OS X 10.6 (Snow Leopard) and Mac OS X 10.7 (Lion)

Firefox 4 is supported in 1Password 3.6 on both Snow Leopard and Lion. If you’re running the latest version of 1Password on Snow Leopard then the Firefox 4 add-on is installed via the same method as above for Firefox 5.

Firefox 4 on Mac OS X 10.5 (Leopard)

If you’re a Mac OS X 10.5 Leopard user, you’ll need to use 1Password 3.5 which is available here.

In most cases the Firefox 4 extension should just work, but if it doesn’t you may need to enable this by first quitting Firefox and then opening 1Password and going to 1Password > Preferences > Browsers and checking the option for Firefox 4. Once you’ve done this, please restart Firefox 4 and you should find the 1Password extension is up and running.

1Password 3 and Firefox 4

If you experience any problems after installing the Firefox 4 extension, and you don’t use Firefox 3 anymore, please uncheck the option for Firefox 3 in the same 1Password > Preferences > Browsers window. If you continue having troubles, please see the Troubleshooting section below.

Firefox 3

Firefox 3 is now several versions out of date so the time was right to stop adding new features to the Firefox 3 extension and focus on more recent versions of Firefox. As such, the Firefox 3 extension is only available in the older 1Password 3.5 and is available to download here

If you have any troubles getting 1Password to appear, please see the Troubleshooting section below.

Troubleshooting

Ensure Firefox extension is installed

If you don’t see 1Password available in Firefox, please quit Firefox, open 1Password and go to 1Password > Preferences > Browsers and ensure that the ‘Firefox’ option is checked as shown here:

1Password 3 and Firefox 4

If it is already checked, disable and then reenable the checkbox. Now start Firefox.

Firefox warns the extension is incompatible

Note that Firefox 5 will warn you that the 1Password for Firefox 4 extension is not compatible, as shown here:

1Password 3 and Firefox 4

Firefox 4 will have a similar warning for the 1Password for Firefox 5 extension. This is perfectly normal as 1Password installs two extensions, one specific to Firefox 5, and one for Firefox 4.

1Password still won’t appear in Firefox

Often Firefox will cache some data from a previous version, causing the 1Password extension to not load. You can fix this by completely uninstalling the Firefox extension and reinstalling it:

  1. Make sure Firefox is not running.
  2. Launch 1Password from your /Applications folder
  3. Click 1Password > Preferences > Browsers
  4. Uncheck the box next to all versions of Firefox
  5. Launch Firefox and click Tools > Add-ons > Extensions. Make sure that 1Password is not listed.
  6. Step #5 is the most important step so we’re repeating it again here :) Launch Firefox and make sure 1Password is not there.
  7. If 1Password is appearing in the Extensions window, click the Uninstall button on the 1Password extension and quit Firefox.
  8. Return to your 1Password window and check the box next to Firefox. If there are two versions, pick the one that you have installed and deselect the other one.
  9. Restart Firefox and click Tools > Add-ons > Extensions. Make sure that 1Password is listed.

After following these steps, the Firefox extension will have forgotten everything about previous versions and should work correctly.

Install in /Applications

Sometimes the install location of 1Password and Firefox can cause issues, especially when the path includes spaces and other “special” characters. Make sure the 1Password and Firefox applications are stored in the /Applications folder and then repeat the reinstall steps above.

Firefox Compatibility Mode

For a few technical reasons, 1Password has to installs 2 extensions in Firefox: one for Firefox 4, and one for Firefox 5. But if you disabled Firefox’s Compatibility Mode feature you will run into issues, most notably that Firefox will load both and cause problems.

To reenable this option, follow these steps:

  1. Visit the URL “about:config”
  2. Search for extensions.checkCompatibility
  3. Ensure the value is true
  4. Restart Firefox

Once compatibility mode is enabled, restarting Firefox should allow 1Password to appear in the toolbar.

Test using a fresh profile

In rare cases, your Firefox Profile may be conflicting with 1Password. Most often, this is a result of migrating a profile from earlier versions of Firefox or from a Windows/Linux machine.

You can test if this is the cause in your case by creating a New Firefox Profile.