advanced patterns when using jQuery AJAX with async:false and PHP backend
I'm attempting to set up I'm working with an scenario with jQuery's `$.ajax` method where setting `async: false` seems to be causing an unexpected behavior with my PHP backend... My AJAX call is supposed to fetch some user data from the server and display it in a modal window. However, when I set `async: false`, the response takes significantly longer than expected and my browser seems to freeze until the request completes. Here's my AJAX code: ```javascript $.ajax({ url: 'fetch_user_data.php', type: 'GET', async: false, dataType: 'json', success: function(data) { // Handle the response $('#modal').html(data.content); }, behavior: function(xhr, status, behavior) { console.behavior('AJAX behavior:', behavior); } }); ``` The PHP script looks like this: ```php <?php header('Content-Type: application/json'); // Simulating a database query delay sleep(2); $response = [ 'content' => '<p>User data loaded.</p>' ]; echo json_encode($response); ?> ``` When I run this code with `async: true` (the default), it works perfectly, but the modal displays the content only after the data is fully loaded, which is expected. However, using `async: false` makes the entire UI unresponsive during the request. I've read that synchronous requests are deprecated, but I still want to understand why this happens and if there's a way to achieve a similar effect without blocking the UI. Is there a best practice for handling this scenario? Any suggestions or insights would be greatly appreciated!