Request: Toggle Ligatures button

**Is your feature request related to a problem? Please describe.**
Ligatures are a big part of some fonts like `Fire Code` however I will be running this font without ligatures and it would of been nice to preview the font without ligatures.

**Describe the solution you'd like**
A toggle button to turn ligatures on/off

**Describe alternatives you've considered**
n/a

**Additional context**
n/a
