[Registry Preview] Allow the "Open Key" button to open a new Registry Editor window for each key

[StevenSchifter]

Description of the new feature / enhancement

Selecting a key in the upper right pane and then clicking the "Open Key" button should be able to open a new Registry Editor window for each key.

Scenario when this would be used?

The user would be able to view multiple registry keys, each in its own window.

Supporting information

According to this answer on Super User, the /m command line argument will allow multiple instances of Registry Editor to be open at a time.