diff --git a/packages/lint/src/rules/composition.test.ts b/packages/lint/src/rules/composition.test.ts
index fcf7457d6..5ac2ad48d 100644
--- a/packages/lint/src/rules/composition.test.ts
+++ b/packages/lint/src/rules/composition.test.ts
@@ -1159,6 +1159,20 @@ describe("composition rules", () => {
       expect(find(result.findings)).toBeUndefined();
     });
 
+    it("does not error when a GSAP timeline is registered with a computed bracket key", async () => {
+      const html = `<html><body>
+        <div data-composition-id="main" data-start="0" data-width="1920" data-height="1080"></div>
+        <script>
+          var spec = { id: "main" };
+          window.__timelines = window.__timelines || {};
+          const tl = gsap.timeline({ paused: true });
+          window.__timelines[spec.id] = tl;
+        </script>
+      </body></html>`;
+      const result = await lintHyperframeHtml(html);
+      expect(find(result.findings)).toBeUndefined();
+    });
+
     it("does not error for a finite CSS animation (runtime auto-infers duration)", async () => {
       const html = `<html><body>
         <div data-composition-id="main" data-start="0" data-width="1920" data-height="1080">
diff --git a/packages/lint/src/rules/gsap.test.ts b/packages/lint/src/rules/gsap.test.ts
index d60992b2d..51f90ff22 100644
--- a/packages/lint/src/rules/gsap.test.ts
+++ b/packages/lint/src/rules/gsap.test.ts
@@ -1296,6 +1296,26 @@ describe("GSAP rules", () => {
     expect(finding).toBeUndefined();
   });
 
+  it("does NOT warn when timeline is registered with a computed bracket key", async () => {
+    const html = `
+<html><body>
+  <div data-composition-id="root" data-width="1920" data-height="1080">
+    <div id="box">Hello</div>
+  </div>
+  <script src="https://cdn.jsdelivr.net/npm/gsap@3/dist/gsap.min.js"></script>
+  <script>
+    var spec = { id: "root" };
+    window.__timelines = window.__timelines || {};
+    const tl = gsap.timeline({ paused: true });
+    tl.to("#box", { opacity: 0.5, duration: 2 });
+    window.__timelines[spec.id] = tl;
+  </script>
+</body></html>`;
+    const result = await lintHyperframeHtml(html);
+    const finding = result.findings.find((f) => f.code === "gsap_timeline_not_registered");
+    expect(finding).toBeUndefined();
+  });
+
   it("does NOT warn for sub-compositions (template-based)", async () => {
     const html = `
 <template>
diff --git a/packages/lint/src/utils.ts b/packages/lint/src/utils.ts
index 60296d2f0..86f053b4a 100644
--- a/packages/lint/src/utils.ts
+++ b/packages/lint/src/utils.ts
@@ -28,8 +28,16 @@ export const TIMELINE_REGISTRY_OBJECT_LITERAL_PATTERN =
   /window\.__timelines\s*=\s*\{\s*(?:["'][^"']+["']|[A-Za-z_$][\w$]*)\s*:/i;
 export const TIMELINE_REGISTRY_ASSIGN_PATTERN =
   /window\.__timelines(?:\[[^\]]+\]|\.[A-Za-z_$][\w$]*)\s*=/i;
+// The bracket branch accepts either a quoted string key (`["root"]`) or a
+// computed key (`[spec.id]`, `[id]`) — a bare-identifier-only bracket branch
+// missed `window.__timelines[spec.id] = tl`, a pattern the shipped
+// code-particle-assemble/code-3d-extrude registry blocks actually use,
+// making gsap_timeline_not_registered false-fire on correctly registered
+// timelines. The computed-key alternative is deliberately non-capturing:
+// its text isn't a literal composition id, so callers reading group 1/2
+// (readRegisteredTimelineCompositionId) must keep falling back to null for it.
 export const WINDOW_TIMELINE_ASSIGN_PATTERN =
-  /window\.__timelines(?:\[\s*["']([^"']+)["']\s*\]|\.\s*([A-Za-z_$][\w$]*))\s*=\s*([A-Za-z_$][\w$]*)/i;
+  /window\.__timelines(?:\[\s*(?:["']([^"']+)["']|[A-Za-z_$][\w$.]*)\s*\]|\.\s*([A-Za-z_$][\w$]*))\s*=\s*([A-Za-z_$][\w$]*)/i;
 export const INVALID_SCRIPT_CLOSE_PATTERN = /<script[^>]*>[\s\S]*?<\s*\/\s*script(?!>)/i;
 
 const TIMELINE_REGISTRY_KEY_PATTERN =
