Double-clicking submit sends two emails.

Much like the title says, users have been clicking multiple times on the submit button, and an email is being sent for each click they get in before the page refreshes from the first click. I tested this myself by clicking non-stop until the page loaded. This generated about 11 emails before the page refresh cut me off.

I know the “easy fix” is to just tell people to click once, but computer-illiteracy is high among my website’s target audience. Scarily enough, this happens way more than it should.

https://wordpress.org/plugins/clean-and-simple-contact-form-by-meg-nicholas/