I remember when someone registered (poopemoji).la

https://xn--ls8h.la/

It does show up as the poop emoji followed by .la in google search results, but not in a firefox address bar.

>but not in a firefox address bar.

That is by design (on Firefox's part) to avoid someone registering e.g. steаmpowered.com (notice а as U+0430 instead of a as U+61) and running a scam that looks valid on the address bar.

Yes absolutely to avoid phishing sites with idn homograph, homoglyph attacks. Personally I'd like to see the punycode first then the emoji