Write: add anon funnel Tracks events + is_anon on editor open (#50216)

* Write: add anon funnel Tracks events + is_anon on editor open

Instruments the two intent steps of the Write On Phase 1 fake-door funnel
that were missing between "land" and "signup":

* wpcom_write_editor_anon_write_start — fires once per session on the first
  real keystroke in the anon editor (guards against empty-editor abandons
  counting as writes).
* wpcom_write_editor_anon_publish_click — fires when an anon visitor hits the
  signup wall at Publish, with word_count, time_to_publish_ms, draft_size_bytes.

Both go through the _tkq queue and share the tk_ai cookie, so they stitch to
the new user at signup completion (identifyUser via the write-on flow's
builtin-auth registration path).

Also adds is_anon to the server-side wpcom_write_editor_open event
((int) ! is_user_logged_in() — anon is the only logged-out render of this
editor), so the funnel can scope its top-of-funnel denominator to anon traffic
without depending on the client-only wpcomWriteIsAnon flag.

READ-560

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Bej2wXzZnmKgdR6v5UHc5J

* Write: also register anon write-start on title input

The title field binds to updateTitle, not repairStructure, so a visitor who
typed only a title would emit anon_publish_click without a preceding
anon_write_start. Hook the title action too, so a title-only author still
registers a write-start.

READ-560

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Bej2wXzZnmKgdR6v5UHc5J

* Write: flush anon publish_click Tracks pixel before the signup redirect

wpcom Tracks sends beacons via new Image(), whose in-flight GET the
browser cancels on unload. wpcom_write_editor_anon_publish_click fires
immediately before window.location.assign() to the signup flow, so a
synchronous redirect could drop the funnel's key conversion event.

Route it through a bounded flush helper that gives the pixel time to
dispatch, then navigate. The wait only applies when the Tracks client
has upgraded the _tkq queue; otherwise it resolves immediately so the
handoff is never stalled for a beacon that won't fire.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WHatptuGFWEvGfGzPDUjfT

---------

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

Committed via a GitHub action: https://github.com/Automattic/jetpack/actions/runs/28818337048

Upstream-Ref: Automattic/jetpack@28b9f52

Author: allilevine

jetpack_vendor/automattic/jetpack-mu-wpcom/CHANGELOG.md

@@ -45,6 +45,7 @@ This is an alpha version! The changes listed here are not final.
 - Show the Help Center icon on the navbar when seeing the Editor with a mobile device.
 - Smart Dictation: Add endpoints to proxy client secret requests.
 - WP.com smart dictation app
+- Write: add anon funnel Tracks events (write-start, publish-click) and an is_anon flag on editor open, for the Write On Phase 1 fake-door funnel.
 - Write: Add a topbar three-dot menu with "Open in block editor" and "Preview" actions when editing an existing post.
 - Write: Add blockquote citation support
 - Write: add full-justification alignment for paragraphs.

jetpack_vendor/automattic/jetpack-mu-wpcom/src/features/write/view.js

@@ -37,6 +37,85 @@ function isAnon() {
 	return typeof window !== 'undefined' && window.wpcomWriteIsAnon === true;
 }
 
+// Approximates the anon editor open — the module loads immediately after the
+// server rendered the page (and fired `wpcom_write_editor_open`). Used as the
+// baseline for `time_to_publish_ms` on the anon publish-click event.
+const ANON_EDITOR_OPENED_AT = typeof Date !== 'undefined' ? Date.now() : 0;
+
+// Guards `wpcom_write_editor_anon_write_start` to once per session.
+let anonWriteStartTracked = false;
+
+/**
+ * Fire a client-side Tracks event via the `_tkq` queue. Anon callers share the
+ * `tk_ai` cookie, so these stitch to the eventual user at signup completion.
+ *
+ * @param {string} name    - Tracks event name.
+ * @param {object} [props] - Optional event properties.
+ */
+function recordTracksEvent( name, props ) {
+	try {
+		window._tkq = window._tkq || [];
+		window._tkq.push( [ 'recordEvent', name, props || {} ] );
+	} catch {
+		// Tracks unavailable — nothing useful to do; swallow.
+	}
+}
+
+// How long to let a Tracks pixel leave the browser before a redirect. wpcom's
+// Tracks client sends via `new Image()`, and the browser cancels in-flight
+// image GETs on unload — so an event fired immediately before navigation can be
+// dropped. 250ms is imperceptible ahead of a full-page handoff to the signup
+// flow, and well within the round-trip a fire-and-forget pixel needs.
+const TRACKS_BEACON_FLUSH_MS = 250;
+
+/**
+ * Fire a Tracks event, then resolve once the pixel has had time to leave the
+ * browser — for events recorded immediately before navigating away (e.g. the
+ * anon publish handoff), where a synchronous redirect would otherwise cancel
+ * the in-flight `new Image()` beacon. Best-effort and bounded: if the Tracks
+ * client hasn't upgraded the queue (nothing will send), it resolves at once so
+ * the handoff is never delayed for a beacon that won't fire.
+ *
+ * @param {string} name    - Tracks event name.
+ * @param {object} [props] - Optional event properties.
+ * @return {Promise<void>} Resolves when it is safe to navigate.
+ */
+function recordTracksEventBeforeUnload( name, props ) {
+	recordTracksEvent( name, props );
+
+	// The real Tracks client replaces `_tkq.push`; until it does, pushes just
+	// pile up in a plain array and no pixel is sent, so there's nothing to wait
+	// for. (This is exactly the pre-loader state we saw on the anon surface.)
+	const tracksActive =
+		typeof window !== 'undefined' && !! window._tkq && window._tkq.push !== Array.prototype.push;
+
+	if ( ! tracksActive || typeof setTimeout === 'undefined' ) {
+		return Promise.resolve();
+	}
+
+	return new Promise( resolve => {
+		setTimeout( resolve, TRACKS_BEACON_FLUSH_MS );
+	} );
+}
+
+/**
+ * Fire `wpcom_write_editor_anon_write_start` once, the first time an anon
+ * visitor types real content. Keeps the funnel's write-through step honest —
+ * an empty editor that's opened and abandoned shouldn't count as a write.
+ *
+ * @param {string} text - Current plain-text content of the editor.
+ */
+function maybeTrackAnonWriteStart( text ) {
+	if ( anonWriteStartTracked || ! isAnon() ) {
+		return;
+	}
+	if ( ! text || ! text.trim() ) {
+		return;
+	}
+	anonWriteStartTracked = true;
+	recordTracksEvent( 'wpcom_write_editor_anon_write_start' );
+}
+
 /**
  * Persist the current draft snapshot to localStorage under the anon key.
  *
@@ -3458,6 +3537,13 @@ const { state } = store( 'wpcom-write', {
 			el.ref.style.height = 'auto';
 			el.ref.style.height = el.ref.scrollHeight + 'px';
 
+			// Typing a title counts as the first anon write too — the title field
+			// binds to this action rather than repairStructure, so hook it here so
+			// a title-only author still registers a write-start before publish.
+			if ( isAnon() && ! anonWriteStartTracked ) {
+				maybeTrackAnonWriteStart( state.title );
+			}
+
 			// Dismiss the recovery banner once the user starts editing.
 			if ( state.showRecoveryBanner ) {
 				localStorage.removeItem( AUTOSAVE_STORAGE_KEY );
@@ -3673,6 +3759,12 @@ const { state } = store( 'wpcom-write', {
 			promoteGapAtCursor();
 			ensureBlockStructure();
 			pushToUndoHistoryDebounced();
+
+			// First real keystroke in the anon funnel — fires once per session.
+			if ( isAnon() && ! anonWriteStartTracked ) {
+				const contentEl = getContent();
+				maybeTrackAnonWriteStart( contentEl ? contentEl.textContent : '' );
+			}
 		},
 
 		undo() {
@@ -5782,6 +5874,16 @@ const { state } = store( 'wpcom-write', {
 
 		async publish() {
 			if ( isAnon() ) {
+				// The publish-intent event — the moment an anon visitor hits the
+				// signup wall. Captured before navigating away so it isn't lost to
+				// the handoff. word_count / draft_size_bytes size the draft; the
+				// server open event and this share the tk_ai identity for stitching.
+				const contentEl = getContent();
+				const rawHtml = contentEl ? contentEl.innerHTML : '';
+				const plainText = contentEl ? contentEl.textContent || '' : '';
+				const words = plainText.trim() ? plainText.trim().split( /\s+/ ).length : 0;
+				const draftContent = rawHtml ? convertToBlocks( rawHtml ) : '';
+
 				// Flush the latest draft snapshot before navigating — autosave is
 				// on a 30s tick, and a fast typer-then-clicker would otherwise
 				// hand off stale (or no) content to the signup flow.
@@ -5791,6 +5893,18 @@ const { state } = store( 'wpcom-write', {
 				// internal navigation in this file does (cf. openInBlockEditor).
 				allowLeave = true;
 
+				// Record publish-intent and let the pixel dispatch before the
+				// redirect. wpcom Tracks beacons via `new Image()`, whose in-flight
+				// GET the browser cancels on unload — so a synchronous navigate
+				// would drop this event. The wait is bounded (and skipped entirely
+				// when Tracks isn't loaded) so the handoff is never stalled.
+				await recordTracksEventBeforeUnload( 'wpcom_write_editor_anon_publish_click', {
+					word_count: words,
+					time_to_publish_ms: Date.now() - ANON_EDITOR_OPENED_AT,
+					draft_size_bytes:
+						typeof Blob !== 'undefined' ? new Blob( [ draftContent ] ).size : draftContent.length,
+				} );
+
 				// Anon visitors hand off to the signup flow, which reads the draft
 				// from localStorage and publishes after signup completes.
 				window.location.assign( 'https://wordpress.com/setup/write-on' );

jetpack_vendor/automattic/jetpack-mu-wpcom/src/features/write/write.php

@@ -817,6 +817,11 @@ function wpcom_write_render_admin_page() {
 		$event_props = array(
 			'is_new_post' => (int) ( 0 === $edit_post_id ),
 			'source'      => $source,
+			// Anon entry is the only logged-out render of this editor (the wp-admin
+			// page requires auth), so logged-out is a reliable proxy for the anon
+			// fake-door funnel. Lets the funnel scope its top-of-funnel denominator
+			// to anon traffic without depending on the client-only wpcomWriteIsAnon flag.
+			'is_anon'     => (int) ! is_user_logged_in(),
 		);
 
 		if ( $edit_post_id > 0 ) {

jetpack_vendor/i18n-map.php

@@ -62,7 +62,7 @@
     ),
     'jetpack-mu-wpcom' => array(
       'path' => 'jetpack_vendor/automattic/jetpack-mu-wpcom',
-      'ver' => '6.11.0-alpha1783360822',
+      'ver' => '6.11.0-alpha1783366870',
     ),
     'jetpack-password-checker' => array(
       'path' => 'jetpack_vendor/automattic/jetpack-password-checker',