Internal objects of the SumDoc application window

Trust boundary

These objects exist only inside the SumDoc application’s own window. They won’t be there in Safari, Chrome, in your iframe, or on an arbitrary domain. For embedding, use JSON-line exchange, WebSocket, or the editor surface.

And only inside the document window. The application’s utility windows — the problem report, the assistant — have their own narrow sets of calls, and they deliberately don’t reuse the document window’s common set: such a window needs a handful of calls and nothing from the editor surface. Looking for fastdocShell there is pointless. :::

Object	Purpose	Example methods
window.fastdocShell	Document, editor commands, state, save, menu	getState(), getCurrentDocumentTruth(), openDocxPath(), onStateChanged()
window.a4Update	Application updates	status(), check(), start(), dismiss(), reveal(), openNotes(), onState()
window.a4Help	Version and support	version(), reportProblem(), supportBundle(), checkUpdates(), reportBadge(), onReportBadge()
window.a4Vizor	Notes on the window’s built-in log: it lives in the tab’s memory for about a minute and only leaves together with the problem report	onNote()

Examples inside the application’s own window

const state = await window.fastdocShell.getState();
const truth = await window.fastdocShell.getCurrentDocumentTruth();
const version = await window.a4Help.version();

const stopState = window.fastdocShell.onStateChanged((next) => {
  console.log("document state", next);
});

const stopUpdate = window.a4Update.onState((next) => {
  console.log("update state", next);
});
await window.a4Update.check();

// Be sure to unsubscribe when the component unmounts.
stopState();
stopUpdate();

How to choose the right API

• Writing your own desktop app or a server-side wrapper — use fastdoc-cli serve with JSON-line exchange.
• A shell built on web technologies that needs asynchronous exchange — use serve --ws 0.
• Need to demonstrate embedding on the user’s machine — use the surface command with a WebView window or iframe; editing in this surface is limited to the first paragraph.
• Your product lives in the browser and the core must run on the server — see editor in the browser.
• Modifying the SumDoc application itself — the window’s internal contract, by separate agreement.