The update came several days after Mozilla Foundation issued 14 advisories with eight listed as "critical," two as "high," and four as "moderate." Critical vulnerabilities are especially troublesome as Mozilla defines them as a vulnerability that: can be used to run attacker code and install software, requiring no user interaction beyond normal browsing.
Other than avoiding untrustworthy web sites, being careful of what files are downloaded to the system, and not running software of unknown origin, keeping one's web browser up to date is an important part of keeping a system secure.
Firefox users can see if they're running the latest, and presumably the safest, version of Firefox by selecting "Check for updates" within the Help pull-down.
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