Open the legacy Control Panel "File Associations" (or s.th. similar) in Win10

Beginning with 1803 that feature was removed entirely, with any access to the old feature redirected to the new interface, so to answer directly: No, the interface no longer exists in current Windows 10.

I can't remember where I first saw it suggested, but I was directed to this ancient 3rd party app that gives a similar feature set to the original Win7 interface and still works well under Windows 10:

https://www.nirsoft.net/utils/file_types_manager.html

Alternatively, it may be possible to hand-port the binaries over from an older installation, but I suspect you would then also have to reverse-engineer all of the CLSID redirections to allow it to work.

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