Output windows, Remote Output and Freeze

Commands

The Popup item of the menu shows the hint Alt+B. The key that opens a popup is Alt+Shift+B. The Popup item is hidden on touch-only devices, and the Tab and Remote items stay.

Each command opens out.rtcode.net in a window named O[N], as a popup or as a tab, at the position and size that slot last had. A slot without one starts from the size of the inline output. Every output reports its geometry every second, when it resizes and when it unloads. The playground waits up to 5 seconds for the new window to report that it is ready, and then initializes the output in it.

What happens to the inline output

The first external window replaces the inline output. The frame is removed, so its page state is lost, and the split moves fully to the input. A placeholder reads "Output in external window." ("…windows." with several). Later windows add more outputs. Every output receives the sync updates and the per-document output settings.

The settings and tools that need the inline frame have no effect once it is gone: the fixed viewport, zoom, Auto-fit, Output: Metrics and Fullscreen Output, and the scripting globals that measure or query the inline output. See Which outputs a setting reaches.

Closing windows

Closing the last external window reloads the playground, which brings the inline output back. Reloading or leaving the playground closes every output window it opened.

Popups must be allowed

Output tabs and popups need the browser to allow popups from rtcode.io. Allow them before you open the first output window. If the output does not come back after a blocked window, see Troubleshooting.

Starting a session

1. Press Alt+Q / ⌥+Q. You can also use the palette item New Remote Output…, Open ▸ Output ▸ Remote, or the editor's context menu.
2. A dialog warns: "Remote output is work in progress! <script> edit→load is not implemented. To try it now, 1. click Try 2. open the highlighted URL in remote device/browser". Choose Try, or Cancel.
3. A toast shows the link https://rt.ht/<id>, with rt.ht/<id> highlighted, and a QR code of it. The id is four characters long. Share hands the link to the browser's share sheet, titled "Remote Output", and Cancel or Esc ends the session.
4. Open the link on the other device, or scan the QR code.

The playground waits for a device to join without a time limit. Once the device announces itself, both data channels must open within 10 seconds. The connection uses one WebRTC data channel named sync in each direction, set up through a signaling service.

While a device is connected

When a device connects, a toast names its browser for two seconds, and a card for the session appears in View Remote Outputs. If the connection fails or ends, a toast names the device's browser, the session is removed, and a new session with the same id starts waiting, until you press Cancel. The device itself shows "Remote output terminated! Session lasted <duration>.".

View Remote Outputs… opens with Alt+Y / ⌥+Y, from the palette, or from the cast button that appears in the toolbar, with a count, while sessions exist. Its title is a cast icon and "×N".

Session card

The device's browser, its link (rt.ht/<id>), its location (city, region, country), its IP address, the start time (absolute and relative) and the round trip in milliseconds for a trivial evaluation, or ❌ on a timeout. The location and IP address are looked up from the device with ip.rt.ht.

WebRTC stats

Focusing a card shows the packets and bytes received and sent, the local and remote candidate types and protocols, and the round-trip time. The numbers refresh every 5 seconds while the dialog is open.

Actions

Click a card to end the session, after the confirmation "Terminate this remote output session?" (Terminate). Right click a card to copy its transport stats as JSON.

Limits

• Script edits that need a full output reload are not applied on remote devices.
• Keyboard shortcuts are not forwarded from the remote device.
• Worker requests in an output that is connected only over WebRTC see request.rt.user === null.
• Both devices need WebRTC. Share needs Web Share; where the browser lacks it, you get the link and the QR code only.

Commands

Both commands are in the F1 palette and on the keyboard. They have no menu item.

The keys with ⌘ are for the editor on macOS. Elsewhere on the page, use Ctrl or ⌘ with Alt. The output and the console forward these keys to the playground, but only while their own page still responds, and a hung output cannot forward anything. The console drops ⌘, so on macOS use ⌃+⌥+F and ⌃+⌥+D there.

Because the output runs in a separate origin, and in a separate process where the browser provides one, a runaway loop in it can leave the playground responsive enough to navigate away. If keyboard focus is inside the hung output, click the editor or the toolbar before you press the keys.

The frozen page

Freeze saves the URL state and navigates the playground to frozen.rt.ht, carrying the playground's URL and state. Leaving the page closes the output windows, and the unload guard may ask for confirmation while an Agent Folder Share is active or the URL state is unsaved.

• Heading and message. "Code is frozen!" with "Review scripts for infinite loops." when the code has scripts, and "Code is frozen." with "No scripts; ready to unfreeze." when it has none.
• Button. "Review and unfreeze ›" or "Unfreeze ›". For the first 5 seconds the button is dimmed and has no link. Then it gets its link and takes focus.
• Preview. A non-interactive, color-inverted preview of the code sits beside the text. It is the playground in frozen mode: the editor is read-only, the split is disabled, and no output is created.

Unfreezing

Review and unfreeze ›

Returns to the playground with the editor loaded, but without starting the output. A message that you cannot close reads "Infinite loop? Fix code and reload! Ctrl+R" (⌘+R on macOS), and the editor has focus. The unfreeze flag is removed from the URL at once, so Ctrl+R or any reload then runs the fixed code.

Unfreeze ›

Returns to the same URL and runs the code normally.

Recovering from a runaway loop

Clicking Start in this page hangs the output with an endless loop.

<button id=go>Start</button>
<script>
  go.onclick = () => { for (;;) {} }; // runaway loop: the output hangs after the click
</script>

1. Click into the editor, so keyboard focus leaves the hung output.
2. Press Ctrl+Alt+D / ⌘+⌥+D. Use Ctrl+Alt+F / ⌘+⌥+F to freeze every open playground window.
3. On frozen.rt.ht ("Code is frozen!"), wait 5 seconds and choose Review and unfreeze ›.
4. The playground opens without starting the output and shows "Infinite loop? Fix code and reload!". Remove the loop and press Ctrl+R / ⌘+R.