Also === in JS and TS turning into three horizontal lines is really nice for my brain (even though lint catches it). Fira coda retina is still my go-to font, this one doesn't look quite as legible.

Some of them are a little ambiguous to me. For example, the ligature for #{ looks like it could be #={. I honestly couldn't tell until I selected the text.

Some of them are nice, however. Specifically the ones that just tighten up the spacing and make small adjustments. For example, most of the ones that involve a colon I think are an improvement, but still distinct and unambiguous.