• It's useful to know what version of Firefox you're running in order to debug an issue or simply to ensure that Firefox is up to date. Here's how to figure it out.
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• Click the menu button, then Help, then About Firefox from the drop-down menu. The Firefox About window will display. Underneath the Firefox name is the version number.
• By default, when you open the About Firefox window, an update check will begin. If a newer version of Firefox is available, it will be downloaded automatically.

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