In 2020, when the Chromium-based (open source) Edge was released, Microsoft surprised everyone by offering support for older and outdated operating systems such as Windows 7, 8 and 8.1.
This move by Microsoft seems to be coming to an end as the company is preparing to stop supporting Edge on versions of Windows released before 2015. The latest version of Microsoft Edge Dev is now only available for Windows users 10 and 11.
It's worth noting that stable versions of Microsoft Edge, Chrome, and other Chromium-based browsers still support Windows 7, 8, and 8.1 (Chrome is asking its users to update to Windows 10 or 11).
Developers will stop offering updates for old versions of Windows early next year after Microsoft shuts down the program Extensive security updates for Windows 7.
As for Firefox, Mozilla will have to decide when to stop updating Firefox on pre-Windows 10 systems.