Five Steps to Firefox Security

To take advantage of Firefox’s strong security features, make sure they’re enabled.

Fend off malware, phishers, and their ilk by exercising Firefox's built-in security features.
MANY PEOPLE CONSIDER Mozilla Firefox to be one of the most secure Web browsers. But the amount of protection depends on the settings you have and haven’t configured. Also, you can install countless add-ons to bolster your defenses.

Enable a Master Password

As with Google Chrome, you can view a list of your saved user­names and passwords via the options menu of Firefox. If you employ the same or similar passwords for sensitive sites such as that of your bank, this list can be dangerous.
Fortunately, Firefox offers a master-password feature that encrypts and password-protects the saved-password list. When it's enabled, you must enter the master password the first time you use a saved password, once per browser session. Additional­ly, even though you enter the master password the first time.

you must always enter it before you can view saved passwords via the options menu. This is a great feature to help prevent casual snooping around your passwords, and it even stops most third-party utilities from recovering them as well.
To enable the master-password feature, open the Firefox menu and select Options ► Security ► Use a master password.

Use a Strong Password for Syncing

Firefox offers more security than Google Chrome does when you're setting up a new computer or device to sync. First you must log in with your Firefox Sync password, and then you either enter a random passcode from the new device into one that you’ve already set up, or take the recovery key from a device you've already set up and input it into the new device. Just be sure to use a strong password-one with mixed-case letters, numbers, and special characters. To enable or change sync settings, open the Firefox menu and select Options ► Sync.

Enable Security Options

Like the other popular browsers, Firefox includes some basic security and privacy settings. Though most are enabled by default, you may want to ensure they haven't been disabled.
Open the Firefox menu and select Options. In that window, select the Secu­rity tab. Confirm that the first option, Warn me when sites try to instaii add-ons, is enabled to help prevent sites from automatically installing add-ons, as some can be dangerous. The same goes for Block reported attack sites and Block reported web forgeries, options that can protect against malware and phishing.
Next, select the Privacy tab. For more privacy online, select the first option, Tell websites I do not want to be tracked, which isn't enabled by default.
Then, choose the Content tab. To pre­vent pop-ups, ensure that the Block pop­up windows option is enabled.
Last, select Advanced ► Update ► Auto­matically install updates.

Use Add-ons for Protection

For additional safety consider installing some security-related add-ons (available from addons.mozilla.org):
NoScript helps you control which sites can use JavaScript, Silverlight, and Flash.
Adblock Plus blocks banners, pop-ups, and video advertisements on websites.
Web of Trust (WOT) shows the user ratings of sites and blocks malware and dangerous sites.
HTTPS Finder automatically detects and enforces HTTPS/SSL-encrypted con­nections when available, reducing the chances of an eavesdropper on a Wi-Fi network capturing your login details.
Xpnd.it is a short-URL expander that allows you to hover over shortened links to see the real URL.

Check and Update Plug-ins

Cybercriminals regularly use vulnerabili­ties in popular browser plug-ins to infect and invade computers. Most plug-ins release updates to patch holes. Many automatically update or at least notify you of updates, but it’s a good idea to periodically check for updates yourself. Consider using the Mozilla plug-in check­er.