From c98d6fbac8c423dbdb488499ed6df167a994d96f Mon Sep 17 00:00:00 2001
From: James Russo <james.russo@heygen.com>
Date: Thu, 10 Sep 2026 12:53:30 -0400
Subject: [PATCH] fix: keep caption transcript data inside generated scripts
 (#3847)

* fix: keep caption transcript data inside generated scripts

* test: locate caption data without an HTML filtering regex
---
 .../studio/src/captions/generator.test.ts     | 30 ++++++++++++++
 packages/studio/src/captions/generator.ts     |  8 ++--
 skills-manifest.json                          |  6 +--
 .../faceless-explainer/scripts/captions.mjs   |  4 +-
 skills/pr-to-video/scripts/captions.mjs       |  4 +-
 skills/pr-to-video/scripts/captions.test.mjs  | 41 +++++++++++++++++++
 .../product-launch-video/scripts/captions.mjs |  4 +-
 7 files changed, 85 insertions(+), 12 deletions(-)

diff --git a/packages/studio/src/captions/generator.test.ts b/packages/studio/src/captions/generator.test.ts
index f9b7842425..1e81ef792f 100644
--- a/packages/studio/src/captions/generator.test.ts
+++ b/packages/studio/src/captions/generator.test.ts
@@ -1,5 +1,6 @@
 // @vitest-environment node
 import { describe, it, expect } from "vitest";
+import { Window } from "happy-dom";
 import { generateCaptionHtml } from "./generator";
 import { buildCaptionModel, TranscriptWord } from "./parser";
 
@@ -31,6 +32,35 @@ function buildTestModel(wordsPerGroup = 5) {
 // ---------------------------------------------------------------------------
 
 describe("generateCaptionHtml", () => {
+  it("keeps script-closing text and word IDs as data when HTML is parsed", () => {
+    const text = '</ScRiPt><img src=x onerror="alert(1)"><!-- <script> & end';
+    const id = '</script><svg onload="alert(2)">';
+    const model = buildCaptionModel([{ text, id, start: 0, end: 1 }], {
+      width: 1920,
+      height: 1080,
+      duration: 2,
+      wordsPerGroup: 5,
+    });
+    const window = new Window();
+    const template = window.document.createElement("template");
+    template.innerHTML = generateCaptionHtml(model);
+    const nested = template.content.querySelector("template");
+    expect(nested).not.toBeNull();
+    const content = nested!.content;
+    expect(content.querySelector("img, svg")).toBeNull();
+    const scripts = content.querySelectorAll("script");
+    expect(scripts).toHaveLength(1);
+    const script = scripts[0].textContent;
+    const transcript = script.match(/const TRANSCRIPT = ([\s\S]*?);/);
+    expect(transcript).not.toBeNull();
+    expect(JSON.parse(transcript![1])).toEqual([{ text, id, start: 0, end: 1 }]);
+    const wordText = script.match(/\.textContent = (.*);/);
+    const wordId = script.match(/\.id = (.*);/);
+    expect(JSON.parse(wordText![1])).toBe(text);
+    expect(JSON.parse(wordId![1])).toBe(id);
+    window.close();
+  });
+
   describe("HTML structure", () => {
     it("wraps output in a <template id='captions-template'>", () => {
       const model = buildTestModel();
diff --git a/packages/studio/src/captions/generator.ts b/packages/studio/src/captions/generator.ts
index 44b8ed075d..bdfc38be8a 100644
--- a/packages/studio/src/captions/generator.ts
+++ b/packages/studio/src/captions/generator.ts
@@ -277,7 +277,7 @@ function generateJs(model: CaptionModel): string {
     }
   }
 
-  const transcriptJson = JSON.stringify(allSegments, null, 2);
+  const transcriptJson = JSON.stringify(allSegments, null, 2).replace(/</g, "\\u003c");
 
   const groupBlocks: string[] = [];
 
@@ -303,9 +303,11 @@ function generateJs(model: CaptionModel): string {
 
     // Build word spans
     const wordLines: string[] = groupSegments.map((seg) => {
-      const escaped = JSON.stringify(seg.text);
+      const escaped = JSON.stringify(seg.text).replace(/</g, "\\u003c");
       const segVar = `w_${seg.id.replace(/[^a-zA-Z0-9_]/g, "_")}`;
-      const idLine = seg.wordId ? `\n  ${segVar}.id = ${JSON.stringify(seg.wordId)};` : "";
+      const idLine = seg.wordId
+        ? `\n  ${segVar}.id = ${JSON.stringify(seg.wordId).replace(/</g, "\\u003c")};`
+        : "";
       return (
         `  const ${segVar} = document.createElement('span');` +
         `\n  ${segVar}.className = 'word clip';` +
diff --git a/skills-manifest.json b/skills-manifest.json
index de75b0ba2a..75da4abbfa 100644
--- a/skills-manifest.json
+++ b/skills-manifest.json
@@ -6,7 +6,7 @@
       "files": 142
     },
     "faceless-explainer": {
-      "hash": "986ee23676272292",
+      "hash": "76162336b4c88963",
       "files": 24
     },
     "figma": {
@@ -62,11 +62,11 @@
       "files": 132
     },
     "pr-to-video": {
-      "hash": "4905e50c64aab195",
+      "hash": "265c1f85d732d79c",
       "files": 30
     },
     "product-launch-video": {
-      "hash": "960e964f32dcb4fa",
+      "hash": "3e1efc70cad06b58",
       "files": 30
     },
     "remotion-to-hyperframes": {
diff --git a/skills/faceless-explainer/scripts/captions.mjs b/skills/faceless-explainer/scripts/captions.mjs
index 7e04affe6b..8390686583 100644
--- a/skills/faceless-explainer/scripts/captions.mjs
+++ b/skills/faceless-explainer/scripts/captions.mjs
@@ -263,7 +263,7 @@ function buildFromSkin(skin, groups, total, W, H, tokens, die, faces = "", fonts
   out = fillOnce(
     out,
     /var GROUPS = \[\];/,
-    `var GROUPS = ${JSON.stringify(groups)};`,
+    `var GROUPS = ${JSON.stringify(groups).replace(/</g, "\\u003c")};`,
     "`var GROUPS = [];` hole",
   );
   out = fillOnce(out, /var DURATION = 0;/, `var DURATION = ${total};`, "`var DURATION = 0;` hole");
@@ -480,7 +480,7 @@ function buildCaptionsHtml(groups, total, W, H) {
   <script src="https://cdn.jsdelivr.net/npm/gsap@3.14.2/dist/gsap.min.js" integrity="sha384-sG0Hv1tP1lZCk9KQmrIbY/XNwi+OY84GQqhMscbnsoBFqAz8KNCil1kvfL3Hbbk2" crossorigin="anonymous"></script>
   <script>
     (function () {
-      var GROUPS = ${JSON.stringify(groups)};
+      var GROUPS = ${JSON.stringify(groups).replace(/</g, "\\u003c")};
       var cap = document.getElementById("cap");
       var tl = gsap.timeline({ paused: true });
       GROUPS.forEach(function (g) {
diff --git a/skills/pr-to-video/scripts/captions.mjs b/skills/pr-to-video/scripts/captions.mjs
index 7e04affe6b..8390686583 100644
--- a/skills/pr-to-video/scripts/captions.mjs
+++ b/skills/pr-to-video/scripts/captions.mjs
@@ -263,7 +263,7 @@ function buildFromSkin(skin, groups, total, W, H, tokens, die, faces = "", fonts
   out = fillOnce(
     out,
     /var GROUPS = \[\];/,
-    `var GROUPS = ${JSON.stringify(groups)};`,
+    `var GROUPS = ${JSON.stringify(groups).replace(/</g, "\\u003c")};`,
     "`var GROUPS = [];` hole",
   );
   out = fillOnce(out, /var DURATION = 0;/, `var DURATION = ${total};`, "`var DURATION = 0;` hole");
@@ -480,7 +480,7 @@ function buildCaptionsHtml(groups, total, W, H) {
   <script src="https://cdn.jsdelivr.net/npm/gsap@3.14.2/dist/gsap.min.js" integrity="sha384-sG0Hv1tP1lZCk9KQmrIbY/XNwi+OY84GQqhMscbnsoBFqAz8KNCil1kvfL3Hbbk2" crossorigin="anonymous"></script>
   <script>
     (function () {
-      var GROUPS = ${JSON.stringify(groups)};
+      var GROUPS = ${JSON.stringify(groups).replace(/</g, "\\u003c")};
       var cap = document.getElementById("cap");
       var tl = gsap.timeline({ paused: true });
       GROUPS.forEach(function (g) {
diff --git a/skills/pr-to-video/scripts/captions.test.mjs b/skills/pr-to-video/scripts/captions.test.mjs
index 097623bd0d..14aefb8d4b 100644
--- a/skills/pr-to-video/scripts/captions.test.mjs
+++ b/skills/pr-to-video/scripts/captions.test.mjs
@@ -1,4 +1,5 @@
 import assert from "node:assert/strict";
+import { execFileSync } from "node:child_process";
 import { mkdirSync, mkdtempSync, readdirSync, readFileSync, rmSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
@@ -217,3 +218,43 @@ test("every build-frame.mjs copy stages the style axis it promises", () => {
     );
   }
 });
+
+for (const workflow of ["pr-to-video", "faceless-explainer", "product-launch-video"]) {
+  for (const skin of [null, skins[0]]) {
+    test(`${workflow} ${skin ? "skin" : "default"} keeps transcript markup inside script data`, () => {
+      const project = mkdtempSync(join(tmpdir(), "caption-script-data-"));
+      const text = '</ScRiPt><img src=x onerror="alert(1)"><!-- <script> & end';
+      try {
+        writeFileSync(
+          join(project, "STORYBOARD.md"),
+          "---\nformat: 1920x1080\nmessage: T\n---\n\n## Frame 1 — A\n- duration: 3s\n- src: compositions/frames/01-a.html\n",
+        );
+        writeFileSync(
+          join(project, "audio_meta.json"),
+          JSON.stringify({
+            voices: [{ frame: 1, words: [{ text, start: 0, end: 1 }] }],
+          }),
+        );
+        if (skin) writeFileSync(join(project, "caption-skin.html"), skin.source);
+        const script = fileURLToPath(
+          new URL(`../../${workflow}/scripts/captions.mjs`, import.meta.url),
+        );
+        execFileSync(process.execPath, [script, "build", "--hyperframes", project]);
+        const html = readFileSync(join(project, "compositions/captions.html"), "utf8");
+        const start = html.indexOf("var GROUPS =");
+        assert.ok(start >= 0, "generated caption data exists");
+        const end = html.toLowerCase().indexOf("</script", start);
+        assert.ok(end > start, "generated script has a closing tag");
+        const inline = html.slice(start, end);
+        assert.ok(!html.includes("<img"), "transcript cannot create an HTML element");
+        const data = inline.match(/var GROUPS = (.*);/);
+        assert.ok(data, "entire data assignment remains inside the script element");
+        const groups = JSON.parse(data[1]);
+        assert.equal(groups[0].text, text);
+        assert.equal(groups[0].words[0].text, text);
+      } finally {
+        rmSync(project, { recursive: true, force: true });
+      }
+    });
+  }
+}
diff --git a/skills/product-launch-video/scripts/captions.mjs b/skills/product-launch-video/scripts/captions.mjs
index 7e04affe6b..8390686583 100644
--- a/skills/product-launch-video/scripts/captions.mjs
+++ b/skills/product-launch-video/scripts/captions.mjs
@@ -263,7 +263,7 @@ function buildFromSkin(skin, groups, total, W, H, tokens, die, faces = "", fonts
   out = fillOnce(
     out,
     /var GROUPS = \[\];/,
-    `var GROUPS = ${JSON.stringify(groups)};`,
+    `var GROUPS = ${JSON.stringify(groups).replace(/</g, "\\u003c")};`,
     "`var GROUPS = [];` hole",
   );
   out = fillOnce(out, /var DURATION = 0;/, `var DURATION = ${total};`, "`var DURATION = 0;` hole");
@@ -480,7 +480,7 @@ function buildCaptionsHtml(groups, total, W, H) {
   <script src="https://cdn.jsdelivr.net/npm/gsap@3.14.2/dist/gsap.min.js" integrity="sha384-sG0Hv1tP1lZCk9KQmrIbY/XNwi+OY84GQqhMscbnsoBFqAz8KNCil1kvfL3Hbbk2" crossorigin="anonymous"></script>
   <script>
     (function () {
-      var GROUPS = ${JSON.stringify(groups)};
+      var GROUPS = ${JSON.stringify(groups).replace(/</g, "\\u003c")};
       var cap = document.getElementById("cap");
       var tl = gsap.timeline({ paused: true });
       GROUPS.forEach(function (g) {