My first thought: This is neat!
My second thought: What is wrong with me?
I don't know how I've missed the contenteditable attribute for this long. That is absolutely amazing and has really solid browser support as well.
Off the top of my head I'm thinking about replacing with a on simple forms and then you've got an editable area that will automatically resize vertically with your content.
Neat. Styling a
<style>tag seems crazy enough!
Nice idea. Adding transition makes it nice too.
Ok, that's pretty clever.
Very cool. Might actually use this in an upcoming project.