document separate output panes

Author: Jake Donham

README.md

@@ -57,9 +57,13 @@ cell (e.g. to avoid colliding with another definition), define it inside a block
 
 Re-executing a cell that defines variables used in other cells will cause the
 dependent cells to be re-executed automatically. If you don't want this behavior
-for some reason (e.g. you have a long-running cell) you can use the pause button
-in the cell status bar; or if you want to turn it off globally you can uncheck
-the "Vitale: Rerun Cells When Dirty" setting.
+for some reason (e.g. you have a long-running cell) you can use the <img
+src="data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIxZW0iIGhlaWdodD0iMWVtIiB2aWV3Qm94PSIwIDAgMTYgMTYiPjxwYXRoIGZpbGw9ImN1cnJlbnRDb2xvciIgZD0iTTQuNSAzSDZ2MTBINC41em03IDB2MTBIMTBWM3oiLz48L3N2Zz4="
+/> / <img
+src="data:image/svg+xml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHdpZHRoPSIxZW0iIGhlaWdodD0iMWVtIiB2aWV3Qm94PSIwIDAgMTYgMTYiPjxwYXRoIGZpbGw9ImN1cnJlbnRDb2xvciIgZmlsbC1ydWxlPSJldmVub2RkIiBkPSJtNC4yNSAzbDEuMTY2LS42MjRsOCA1LjMzM3YxLjI0OGwtOCA1LjMzNGwtMS4xNjYtLjYyNHptMS41IDEuNDAxdjcuODY0bDUuODk4LTMuOTMyeiIgY2xpcC1ydWxlPSJldmVub2RkIi8+PC9zdmc+"
+/> buttons in the cell status bar to pause and restart execution; or if you want
+to turn it off globally you can uncheck the "Vitale: Rerun Cells When Dirty"
+setting.
 
 ## Importing modules
 
@@ -89,6 +93,11 @@ and Modes](https://vitejs.dev/guide/env-and-mode.html).
 Since code in cells is transformed by Vite, you need to prefix variables with
 `VITE_` in order for them to be visible.
 
+## Output panes
+
+Cell output is displayed below the cell. You can open the output in a separate
+pane by clicking the <img src="data:image/svg+xml;base64,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"/> button in the cell toolbar. Output in a separate pane is updated when the cell is reëxecuted or when dependencies change.
+
 ## Rendering different MIME types
 
 `vitale` inspects the output value and tries to pick an appropriate MIME type to