fix(browser): Try multiple options for lazyLoadIntegration script p…

…arent element lookup (#13717)

Change the order for looking up parent elements to inject the integration script:

1. `document.body`
2. `document.head`
3. `document.currentScript.parentElement`

packages/browser/src/utils/lazyLoadIntegration.ts

@@ -68,7 +68,14 @@ export async function lazyLoadIntegration(
  script.addEventListener('error', reject);
  });
 
- WINDOW.document.body.appendChild(script);
+ const currentScript = WINDOW.document.currentScript;
+ const parent = WINDOW.document.body || WINDOW.document.head || (currentScript && currentScript.parentElement);
+
+ if (parent) {
+ parent.appendChild(script);
+ } else {
+ throw new Error(`Could not find parent element to insert lazy-loaded ${name} script`);
+ }
 
  try {
  await waitForLoad;