When the registration button is clicked, sometimes the registration takes too long (3-4 seconds). The user doesn't know what happened and starts clicking on something else and misses the message that the account has been created and that they need to activate the account from their email.

How to change the "Create Account" button text with an onclick or onsubmit event to something like "Submitting..." or "Please wait..." ?

It might be better to show some sort of animated icon to show the user that the button has been clicked and to wait a second or two?

@mm707
You could add onclick event to add loading or disabled class.
Anyway it should be very quick and if it takes 4 seconds, then most probably mail server is quite slow and blocks you.