diff --git a/apps/desktop/e2e/launch-packaged-app.spec.ts b/apps/desktop/e2e/launch-packaged-app.spec.ts
index cfb4202d33026..a8083f0e5cee7 100644
--- a/apps/desktop/e2e/launch-packaged-app.spec.ts
+++ b/apps/desktop/e2e/launch-packaged-app.spec.ts
@@ -46,6 +46,46 @@ test('renderer loads and shows DOM content', async () => {
   expect(childCount).toBeGreaterThan(0)
 })
 
+test('HUD composer remains fully inside the transparent window', async () => {
+  const hudPagePromise = fixture!.app.waitForEvent('window')
+
+  await fixture!.page.evaluate(() =>
+    (window as typeof window & {
+      hermesDesktop?: { hud?: { open: (options: { sessionId: null }) => Promise<void> } }
+    }).hermesDesktop?.hud?.open({ sessionId: null })
+  )
+
+  const hudPage = await hudPagePromise
+  await hudPage.waitForSelector('[data-slot="composer-rich-input"]', { state: 'visible' })
+
+  const geometry = await hudPage.evaluate(() => {
+    const dock = document.querySelector<HTMLElement>('[data-slot="composer-dock"]')
+    const input = document.querySelector<HTMLElement>('[data-slot="composer-rich-input"]')
+
+    if (!dock || !input) {
+      throw new Error('HUD composer did not render')
+    }
+
+    const dockRect = dock.getBoundingClientRect()
+    const inputRect = input.getBoundingClientRect()
+
+    return {
+      viewportWidth: window.innerWidth,
+      dockLeft: dockRect.left,
+      dockRight: dockRect.right,
+      inputLeft: inputRect.left,
+      inputRight: inputRect.right,
+    }
+  })
+
+  expect(geometry.dockLeft).toBeGreaterThanOrEqual(0)
+  expect(geometry.inputLeft).toBeGreaterThanOrEqual(0)
+  expect(geometry.dockRight).toBeLessThanOrEqual(geometry.viewportWidth)
+  expect(geometry.inputRight).toBeLessThanOrEqual(geometry.viewportWidth)
+
+  await hudPage.close()
+})
+
 test('boot progress overlay fades out or shows error state', async () => {
   const page = fixture!.page
   await page.waitForFunction(
diff --git a/apps/desktop/src/styles.css b/apps/desktop/src/styles.css
index 66c42fe9da12c..ff24c509d8af0 100644
--- a/apps/desktop/src/styles.css
+++ b/apps/desktop/src/styles.css
@@ -2715,7 +2715,11 @@ button[data-slot='aui_msg-reactions'] svg {
   width: 100% !important;
   max-width: none !important;
   transform: none !important;
-  translate: none !important;
+  /* Keep this value indirect. Lightning CSS folds literal identity values into
+     `transform: translate(0)`, which does not override Tailwind's standalone
+     `translate: -50%`; the dock then starts half a HUD width off-screen. */
+  --hud-composer-translate: 0;
+  translate: var(--hud-composer-translate) !important;
   padding: 0 !important;
 }