Captcha Showed as Undefined Image
If the captcha in the post comment section won’t showed, you may try going to include/plugin/really-simple-captcha folder.
And try setting the tmp folder permission to 755 ( or 777 for some server. )
Removing Captcha (Only for the theme from modernize to incidental )
Going to function.php file.
Try searching for
and remove all of the line that contain these word out. ( For some theme, there’re 2 contiguous lines for each keyword. )