Why Contact Form 7 does not work on iOS

Recently, on the WordPress site, I noticed the problem of sending messages via Contact Form 7 from devices with the iOS operating system.
If you used Google reCAPTCHA, when you clicked on the Send button, the page was updated for a very long time and reCAPTCHA reported a wait error, if you disable reCAPTCHA, then the message was sent after 1-2 minutes.

As it turned out, iOS somehow started blocking AJAX, which was used by default when updating the page.

So to solve the problem, I opened the configuration file wp-config.php and just before the line:

define('WP_DEBUG', false);

Added a line:

define ('WPCF7_LOAD_JS', false);

This line prohibits Contact Form 7 from using Javascript.
If you specify this variable at the end of the file, it will not work.

After this, the messages on iOS started to go immediately.