Yes, this comes close.
But problem is:
- can not add a new filetype
- can not add an application (only select from existing list)

So my quest to create the .XYM having 3 openwith entries is...

Yes, I already used that tool. Nice to see which apps can be in the list, but only for existing applications you can enable/disable/remove them.
Not to create a completely new entry in the list.
...

Hi,

Since Windows 8 and now also on Windows 10 I have trouble getting the "old" way of creating the "Open With" context menu working as before.

On all previous Windows versions (up to Win8) it...