clients(lr): modify puppeteer connector to work with new tab targets

clients/lightrider/lightrider-entry.js

@@ -54,15 +54,34 @@ async function getPageFromConnection(connection) {
     undefined /* defaultViewport */,
     undefined /* process */,
     undefined /* closeCallback */,
-    // @ts-expect-error internal property
-    targetInfo => targetInfo._targetId === mainTargetInfo.targetId
+    // eslint-disable-next-line no-unused-vars
+    targetInfo => true
   );
 
-  const pages = await browser.pages();
-  const page = pages.find(p => p.mainFrame()._id === frameTree.frame.id);
-  if (!page) throw new Error('Could not find relevant puppeteer page');
-
-  // @ts-expect-error Page has a slightly different type when importing the browser module directly.
+  // We should be able to find the relevant page instantly, but just in case
+  // the relevant tab target comes a bit delayed, check every time a new
+  // target is seen.
+  /** @type {(value: any) => void} */
+  let resolve;
+  /** @type {(value: Error) => void} */
+  let reject;
+  const promise = new Promise((resolve_, reject_) => {
+    resolve = resolve_;
+    reject = reject_;
+  });
+  browser.waitForTarget(async () => {
+    const pages = await browser.pages();
+    const page = pages.find(p => p.mainFrame()._id === frameTree.frame.id);
+    if (page) {
+      resolve(page);
+      return true;
+    }
+    return false;
+  });
+  const timeoutHandle = setTimeout(() =>
+    reject(new Error('Could not find relevant puppeteer page')), 5000);
+  const page = await promise;
+  clearTimeout(timeoutHandle);
   return page;
 }