Tool to configure Font Linking

[SamHasler]

Description of the new feature / enhancement

I'd like a tool for configuring font linking

in font linking (also called “composite fonts”) it is possible to link one or more fonts (called "linked fonts") to another font (called the "base font"). Once you link fonts, you can use the base font to display code points that do not exist in the base font, but that do exist in one of the linked fonts.

Scenario when this would be used?

This would be particularly useful for configuring monospace/code fonts that also include emojis and powerline glyphs.

Supporting information

See https://docs.microsoft.com/en-us/globalization/input/font-technology#font-linking