When people tell me that I can't (they mean shouldn't) parse HTML with a regex, I say "hold my beer". It isn't a matter of skill or attitude so much as convenience. Doing it the right way was not always so easy (I remember HTML 0.9 being a big deal). Lately, though, I've been using Mojo::DOM to do it for me. It's easier than the old, expedient way.
Create new, complex Promises by composing Promises
Mojolicious 7.49 added an its own implementation of the Promises/A+ specification. mohawk wrote about these in Day 14: You Promised To Call! of the 2017 Mojolicious Advent Calender where he showed you how to fetch many webpages concurrently. This Advent entry extends that with more Promise tricks.