ns-ui / textarea-autosize-swell

It rises like it's proofing.

Type and it swells open line by line. Paste a paragraph and it takes one slow continuous breath instead of popping open. Delete it back down and the fall is slower still, so nothing ever snaps under the cursor.

grows in 180ms, shrinks in 320ms, a big paste breathes open over 400ms — same curve, three different weights