Windows 10 reached EOS (end of support) on October 14, 2025. For more information, see this article.

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Rules and guidelines for using the Mozilla Support site.

What you need to know about Firefox customization with the userChrome.css file and how to help users get more help or revert their changes.

This article explains how to use Bugzilla to report and explain issues you encounter into something a Mozilla engineer can work with.

Learn about the Mozilla Support (SUMO) team.

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