When a user opens or closes the <details> element, the ontoggle event fires. You can try to run the following code to implement ontoggle event attribute −
Example
<!DOCTYPE html> <html> <body> <h2>Details</h2> <p>You need to join office from Feb23<p> <details ontoggle="display()"> <summary>More Information</summary> <p>Timings: 9 to 5:30</p> <p>Office location: Hyderabad</p> </details> <script> function myFunction() { alert("Timings, office location, etc"); } </script> </body> </html>