Loading issue due to extra captcha call

My client has a website that shows a logo when the page is loading. The page has a contact form (Contact Form 7) with Really Simple CAPTCHA enabled – and the page load is super slow (>3 seconds).

Looking at the dev console, I always see a failed call to wp-content/uploads/wpcf7_captcha/1568966865.png that takes ~3 seconds, causing the page to show the loading logo for too long. There is always a subsequent successful CAPTCHA call and captcha works correctly when submitting the form.

Because there is always that 1568966865.png call (and interestingly, the file name is always the same in this first call), the page looks really unresponsive.

What is the reason for this first call to captcha and can this be removed? I actually see the same issue in your documentation (https://contactform7.com/captcha/ – you can always see three failed calls, for three captchas loading).

I’d be happy to contribute a fix to this if possible.