Starting with Firefox version 49, Firefox requires Mac OS X 10.9 (Mavericks) or higher. Visit this Apple Support page to find your Mac OS version.

Mac Os X 10.7.5 Upgrade
If you're using an outdated version of Firefox on Mac OS X 10.8 (Mountain Lion) or earlier, the only way you can update Firefox to a secure version is to upgrade your Mac OS to a version that Apple supports. Visit this Apple Support page to learn more about upgrading your Mac.
Amongst the features that have been or will be present on the new Mac OS X 10.7, Lion (and presumably future Mac OS) are multi-touch gestures, the App Store, App Store, Full Screen Apps, Auto Save. It includes all the file versions available to download off Uptodown for that app. Download rollbacks of Google Chrome for Mac. Any version of Google Chrome distributed on Uptodown is completely virus-free and free to download at no cost. 87.0.4280.88 Dec 3rd, 2020. 87.0.4280.66 Nov 18th, 2020.
While insecure versions of Firefox will continue to work on OS X 10.8 and earlier, using an up-to-date version of Firefox on a supported version of Mac OS will provide you with the best and safest user experience.
Google's new browser is now available for Mac
Older versions of Google Chrome
It's not uncommon for the latest version of an app to cause problems when installed on older smartphones. Sometimes newer versions of apps may not work with your device due to system incompatibilities. Until the app developer has fixed the problem, try using an older version of the app. If you need a rollback of Google Chrome, check out the app's version history on Uptodown. It includes all the file versions available to download off Uptodown for that app. Download rollbacks of Google Chrome for Mac. Any version of Google Chrome distributed on Uptodown is completely virus-free and free to download at no cost.
Google Chrome Mac Os 10.7.5
Mac Os X 10.7.5 Update
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