Something I like about using the inter font is when you do → it turns into an arrow. Coda also does this as well:
However when I do the same inside a link it doesn’t… 
Its a super small thing but would make my inner child very happy to have these formatted as they are when you write plain text!
You can always copy-paste 
It’s not a font feature, it’s a “replacement” feature of Coda itself. Not only arrows, but typographic quotation marks, long dashes instead of hyphens etc. It only does this in non-code-style and non-formula contexts but you can always copy the resulting characters and use them wherever.