The Adobe Flash uninstaller is NOT working on Microsoft Edge running on Windows 10 Pro version 2004.

There are 2 versions of Edge possible on Windows 10 2004, the old version (single-color blue "e" icon) and the new version (blue and green "wave" icon). You probably have the new version since it was released through Windows update.

For the new (Chromium) Edge, version 88 (stable channel) should be released this week according to https://docs.microsoft.com/en-us/deployedge/microsoft-edge-release-schedule#release-schedule and it will remove the bundled Flash version. You can check for updates by typing "edge://help" (without quotes) in the address bar.

For old Edge (and internet explorer), Microsoft has published an update KB4577586 ( https://support.microsoft.com/en-us/help/4577586/update-for-removal-of-adobe-flash-player ) to remove Flash, but it has not been released to Windows update yet. It's possible to manually install it now using the Windows update catalog link in that article (the version for 2004 is on the 2nd page of the catalog results) but it's probably simpler to just let Windows update take care of it when it's released there.