If you want to remove an installation of Firefox, the first thing is to research where it is installed. Because you probably want to remove it manually rather than trusting the uninstaller to choose the one you want to remove. Here's how:

Start the first Firefox and open the Troubleshooting Information page from the Help menu. Either:

• menu button > Help > More Troubleshooting Information
• (menu bar) Help > More Troubleshooting Information

The first section of the page has some key information, including your current Firefox version and "Application Binary," which shows you where Firefox is running from.

Keeping that page open, launch the second Firefox and open its Troubleshooting Information page for comparison. Presumably they are in different locations.

If they are in different locations: Where is the unwanted installation?

If they are not in different locations: Compare the "Profile Folder" rows on the two pages. One of those is an extra profile you don't care about and one has your valuable data. Make a note of which is which and we'll come back to the question of making sure that you always get the one you want.

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