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Simply open Firefox and then click on the options button ( ). It is easy to find out which version of Mozilla Firefox is running on your system. To download 64-bit versions of other versions, follow these links – Firefox ESR | Beta | Developer | Nightly Check if you have 32-bit or 64-bit version of Firefox Then choose the language and also make sure that you press the download button from the 64-bit column. An online installer for the 64-bit version of Firefox is currently not available. You can grab the 64-bit version in the form of offline installer. So, no user data is lost if a user installs the 64-bit version when the 32-bit version is already installed. Firefox 64-bit will make use of the same user profiles and directories as the 32-bit version. And it is also super easy to upgrade from 32 to 64. To download the 64-bit version of Firefox is a simple and straightforward task.
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Download Links for 64-bit Version of Firefox
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That said, we can expect better Firefox performance by using the 64-bit version on a 64-bit system. From look and feel, the 64-bit version of Firefox is same as the 32-bit version.
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