Pinned

## Off the page

Aftershock draws the week's earthquakes on the page. This piece takes the same feed out of the page. It uses Document Picture-in-Picture, the API that lets a page open a small window that floats above every other app, the way a video does, but with any HTML in it.

## One React tree, two windows

The pinned window is empty when it opens. The page copies its own style sheets into it and renders the ticker there through a React portal, so the ticker is still part of this page's tree: the same state, the same poll a minute, and the same Glitch when a new quake arrives. Close the window, or this tab, and it goes away.

## Where it runs

Document Picture-in-Picture runs in Chrome and Edge on a desktop, and only on a click. Everywhere else the ticker stays in the page and the button says why.