OpenCart Sortable Captcha extension is a high-security validation extension. Basic Captcha and Google reCAPTCHA extensions can now be bypassed by advanced bots. Although Google reCAPTCHA is easy to use, it is no longer impassable, and sometimes verification images can overwhelm people.
OpenCart Sortable Captcha extension provides a high security verification option, although it extends the validation time a bit.
Adding question /answers to multi-language support.
Maximum number of attempts and time constraints (Standby Duration).
Requests sent in a very short time are blocked.
Automatic box height or fixed height.
Verification from registered customers is hidden.
When correct answer is given, hiding validation question in same session.