Ligatures, IMO, make for a bad coding editor experience. No, I do not want >> parsed as a right shift when it's actually used as two adjacent template delimiters. And no, I'm not okay with the inconsistency that results from the usage of different operators from one programming language to another. Want to change a != to a == operator? Enjoy futzing with placing the cursor properly. It's a cute idea, but I found it more annoying to use in practice.

You can always use the original version without ligatures, Fira Mono, available here: https://fonts.google.com/specimen/Fira+Mono

Link to the actual Fira Mono homepage: https://github.com/mozilla/Fira