Currently, there are no plans to drop support for Windows 7. Historically, Mozilla has supported operating systems long as their developers stop, and only stop supporting ancient ones when few users run them.

However, once Windows 7 stops receiving updates it will no longer be safe to use, so you should update to Windows 10 if at all possible.

When the developers decide to stop supporting a specific OS then this is usually because newer Firefox versions use OS API features that are only supported by more recent Windows versions.

See also these articles about stopping support for XP and Vista:

• https://support.mozilla.org/en-US/kb/end-support-windows-xp-and-vista
• https://support.mozilla.org/en-US/kb/your-hardware-no-longer-supported

Hi marcellaphilan, Microsoft also has an Extended Security Update (ESU) program for Windows 7 "Professional" and "Enterprise" if you need to squeeze another year out of Windows 7. It is available through volume licensing, and does not apply to the "Starter" and "Home" editions, or apparently to the "Ultimate" edition.

More info: https://support.microsoft.com/en-us/help/4497181/lifecycle-faq-extended-security-updates

Tyler Downer said

Currently, there are no plans to drop support for Windows 7. Historically, Mozilla has supported operating systems long as their developers stop, and only stop supporting ancient ones when few users run them. However, once Windows 7 stops receiving updates it will no longer be safe to use, so you should update to Windows 10 if at all possible.

WIN 10 is so different from WIN 7 that it means completely re-learning everything when you upgrade. I do not have the time for that at all. (Months of re-learning is not in my programme - I am too busy) I do a lot of research and WIN 7 met all my requirements and Firefox browser was (and still is) ideal for me. I only tried to "upgrade" (Huh!) when I ran into a data volume problem on WIN 7. My mistake! What about Mozilla accepting a deal to take over full support for WIN 7 when Microsoft stops its support and leaping forward as a provider? I am a big researcher by occupation and I need a sensible researcher's platform not a lot of fuddy duddy fancypants extras for WIN 10. So what about it Mozilla? Lets leave WIN 10 behind by light years.

Hi Chancery, I think Mozilla has too many challenges on its hands already to take over supporting Windows 7.

What do you mean by this part:

I only tried to "upgrade" (Huh!) when I ran into a data volume problem on WIN 7.

What is a data volume problem?

If you disabled UAC by setting it to "Never notify" then you may run into some problems caused by differing privilege levels, as described in this article: Drag and Drop errors with Firefox Launcher Process enabled and Windows UAC disabled - How to Fix.

I can confirm Mozilla won't be taking over support of Windows 7. Windows 10 is very functionally the same, but regardless there's no plans on dropping win 7 support for now

My WIN 7 was running very slow when I discovered that Local disc D was accumulating a lot of data and showing completely FULL whenever I checked properties. It did not even expose the details of this data until eventually I discovered that it seemed to be data saved up to each recovery point where you can restore to, during cleanup. Instead of deleting the old recovery point data it simply went on storing it. Avast firewall revealed this problem but it did not stop it from happening continuously and my downloads were always filling up Local disc D far too rapidly providing the storage problem and the resulting slowing down of my PC. When I go back to WIN7 I shall arrange a much greater storage capacity with the help of my engineer. I spoke to WIN 10 help centre and the agent insisted that both Firefox and also Avast were contributing to this problem. Now this will be the third time I have gone back to WIN 7 from WIN10 because of the same problems I mentioned. I DO NOT have the time to re-learn how to use either another new platform or a new Microsoft word app to help me in my research and writing work. I know where everything is on WIN 7 but after six months I still have not learned where everything is on WIN 10 so I need to stop wasting my own time. That is why I don't consider WIN 10 an "upgrade" at all. and what is more it is trying to force me to Chrome instead of Firefox, and other apps I don't even need such as Microsoft Edge - whatever that is! WIN 10 is now pestering me for renewing my license which I don't even understand and it won't even allow me to use Word properly because it says I am not activated. Now I could go on because there are many more problems like this with WIN 10. But it is also slowing down now and "not responding" continuously; just like WIN 7 was doing! By the way I use up to 50 pinned tabs at a time with Firefox and I have a method of using at least 3 separate Firefox Windows to divide my work into Investments, Health research and publishing, etc. So I hope this helps to explain the problem and that Firefox will advance more with its development as a result. Maybe you should develop different kinds of Firefox knowing this.

This isn't a Windows forum so I can't help you with that. I would suggest uninstalling Avast, it's a terrible program, and just use Windows defender and Malwarebytes.

Either way, you can continue to use Firefox on Windows 7 for the time being

Please make backups of your profile folder(s) before any drastic system changes: Back up and restore information in Firefox profiles.