From 5f4ae53b10970ec31ba4aa1b16b5cac5831000f2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miguel=20=C3=81ngel?= <miguel.sierra@heygen.com>
Date: Mon, 25 May 2026 19:31:57 +0000
Subject: [PATCH 1/2] fix(core): revert Function constructor back to inline
 IIFE for composition scripts
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The Function constructor (3bb0d1ef) breaks sub-composition scripts that
call document.getElementById() — the constructor creates functions with
global scope, losing access to the composition-scoped DOM proxy. Native
method calls on proxy-returned elements throw "Illegal invocation".

Reverts to the inline IIFE that preserves the closure over __hfScoped*
variables. The original motivation (handling </script> in source) is
already handled by the compiler's script bundling path.

Closes #1074
---
 packages/core/src/compiler/compositionScoping.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/core/src/compiler/compositionScoping.ts b/packages/core/src/compiler/compositionScoping.ts
index 72e9cbbf8..ba9412f30 100644
--- a/packages/core/src/compiler/compositionScoping.ts
+++ b/packages/core/src/compiler/compositionScoping.ts
@@ -216,7 +216,6 @@ export function wrapScopedCompositionScript(
   const authoredRootIdFormsLiteral = JSON.stringify(
     getAuthoredRootIdSelectorForms(authoredRootId?.trim() || ""),
   );
-  const sourceLiteral = JSON.stringify(source);
   return `(function(){
   var __hfCompId = ${compositionIdLiteral};
   var __hfTimelineCompId = ${timelineCompositionIdLiteral};
@@ -486,8 +485,9 @@ export function wrapScopedCompositionScript(
       });
   var __hfRun = function() {
     try {
-      var __hfScript = Function("document", "gsap", "window", "__hyperframes", ${sourceLiteral});
-      __hfScript.call(window, __hfScopedDocument, __hfScopedGsap, __hfScopedWindow, __hfScopedHyperframes);
+      (function(document, gsap, window, __hyperframes) {
+${source}
+      }).call(window, __hfScopedDocument, __hfScopedGsap, __hfScopedWindow, __hfScopedHyperframes);
     } catch (_err) {
       console.error(__hfErrorLabel, __hfCompId, _err);
     }

From 6d97c3d8212fcdaae3625f25880c0a14bf58556a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Miguel=20=C3=81ngel?= <miguel.sierra@heygen.com>
Date: Mon, 25 May 2026 19:41:14 +0000
Subject: [PATCH 2/2] fix(core): restore IIFE with </script> escaping for
 composition scripts
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The Function constructor (3bb0d1ef) was a security hardening to prevent
</script> injection, but it broke sub-composition DOM proxy scoping.
This restores the inline IIFE (preserving closure scope) while adding
</script> → <\/script> escaping to maintain the injection prevention.

Updates tests to match the new IIFE output shape.

Closes #1074
---
 packages/core/src/compiler/compositionScoping.test.ts | 7 ++++---
 packages/core/src/compiler/compositionScoping.ts      | 2 +-
 packages/core/src/compiler/htmlBundler.test.ts        | 4 ++--
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/packages/core/src/compiler/compositionScoping.test.ts b/packages/core/src/compiler/compositionScoping.test.ts
index 5a0a0cd3a..5d806ccdc 100644
--- a/packages/core/src/compiler/compositionScoping.test.ts
+++ b/packages/core/src/compiler/compositionScoping.test.ts
@@ -572,14 +572,15 @@ window.__afterTimeline = window.__timelines.scene;
     expect(scoped).toContain('[data-composition-id="chrome-overlay"] .child-element');
   });
 
-  it("wraps scoped composition script source as a string literal", () => {
+  it("escapes </script> in scoped composition script source to prevent injection", () => {
     const wrapped = wrapScopedCompositionScript(
       'window.payload = "</script><script>window.pwned = true;</script>";',
       "scene",
     );
 
-    expect(wrapped).toContain('Function("document", "gsap", "window", "__hyperframes", ');
-    expect(wrapped).toContain('\\"</script><script>window.pwned = true;</script>\\"');
+    expect(wrapped).toContain("(function(document, gsap, window, __hyperframes)");
+    expect(wrapped).not.toContain("</script><script>");
+    expect(wrapped).toContain("<\\/script>");
   });
 
   it("wraps unscoped composition script source as a string literal", () => {
diff --git a/packages/core/src/compiler/compositionScoping.ts b/packages/core/src/compiler/compositionScoping.ts
index ba9412f30..8ec81fc2b 100644
--- a/packages/core/src/compiler/compositionScoping.ts
+++ b/packages/core/src/compiler/compositionScoping.ts
@@ -486,7 +486,7 @@ export function wrapScopedCompositionScript(
   var __hfRun = function() {
     try {
       (function(document, gsap, window, __hyperframes) {
-${source}
+${source.replace(/<\/(script)/gi, "<\\/$1")}
       }).call(window, __hfScopedDocument, __hfScopedGsap, __hfScopedWindow, __hfScopedHyperframes);
     } catch (_err) {
       console.error(__hfErrorLabel, __hfCompId, _err);
diff --git a/packages/core/src/compiler/htmlBundler.test.ts b/packages/core/src/compiler/htmlBundler.test.ts
index f955ef5ea..bbf5bfef6 100644
--- a/packages/core/src/compiler/htmlBundler.test.ts
+++ b/packages/core/src/compiler/htmlBundler.test.ts
@@ -758,8 +758,8 @@ describe("bundleToSingleHtml", () => {
     expect(bundled).toContain('[data-composition-id="scene"] .title { color: red; }');
     expect(bundled).toContain("new Proxy(window.document");
     expect(bundled).toContain("new Proxy(__hfBaseGsap");
-    expect(bundled).toContain('Function("document", "gsap", "window", "__hyperframes",');
-    expect(bundled).toContain("tl.to('.title'");
+    expect(bundled).toContain("(function(document, gsap, window, __hyperframes)");
+    expect(bundled).toContain('tl.to(".title"');
   });
 
   it("isolates sibling instances of the same external sub-composition", async () => {