Captcha on comments
Require captcha when posting news or file comments (where comments are enabled).
Captcha on comments
Requires captcha when users post comments on news or file/folder comment surfaces (where comments are enabled).
Where to find it
Admin → Settings → Settings (first tab) → Captcha & abuse → Captcha on forms → Comments
Setting key: comment_captcha_enabled
Uses the selected Captcha provider. Master switches like News comments enabled / Enable file comments still apply — captcha only matters when commenting is allowed.
Common problems
Comments enabled but nobody can post
Captcha verify failing. Check provider keys and the browser console on the live domain.