diff --git a/README.md b/README.md
index 77b4dfa8..2767e223 100644
--- a/README.md
+++ b/README.md
@@ -163,7 +163,7 @@ import puppeteer from 'puppeteer';
   const textSelector = await page.waitForSelector(
     'text/Customize and automate'
   );
-  const fullTitle = await textSelector.evaluate(el => el.textContent);
+  const fullTitle = await textSelector?.evaluate(el => el.textContent);
 
   // Print the full title
   console.log('The title of this blog post is "%s".', fullTitle);
diff --git a/docs/index.md b/docs/index.md
index 77b4dfa8..2767e223 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -163,7 +163,7 @@ import puppeteer from 'puppeteer';
   const textSelector = await page.waitForSelector(
     'text/Customize and automate'
   );
-  const fullTitle = await textSelector.evaluate(el => el.textContent);
+  const fullTitle = await textSelector?.evaluate(el => el.textContent);
 
   // Print the full title
   console.log('The title of this blog post is "%s".', fullTitle);
diff --git a/website/versioned_docs/version-20.1.1/index.md b/website/versioned_docs/version-20.1.1/index.md
index 77b4dfa8..2767e223 100644
--- a/website/versioned_docs/version-20.1.1/index.md
+++ b/website/versioned_docs/version-20.1.1/index.md
@@ -163,7 +163,7 @@ import puppeteer from 'puppeteer';
   const textSelector = await page.waitForSelector(
     'text/Customize and automate'
   );
-  const fullTitle = await textSelector.evaluate(el => el.textContent);
+  const fullTitle = await textSelector?.evaluate(el => el.textContent);
 
   // Print the full title
   console.log('The title of this blog post is "%s".', fullTitle);