When a form is loaded, the CAPTCHA module stores processed versions of the form ID and posted form ID in the form state. It then checks that these two values match before releasing the CAPTCHA session ID for use.
_captcha_get_posted_captcha_info() will always follow the "else" path on submission and find the form's actual posted form ID.This is definitely an atypical form architecture, but it's technically allowed by Drupal.
$form_state->setCache(TRUE); in its ::buildForm() implementation)._captcha_get_posted_captcha_info() is always NULL.Instead of pulling the posted form ID from the form state, just simply reference this_form_id in the form state. This is safe to do because a cached form state will never be paired to a form with a different ID.
None.
None.
None to this module's public API.
Needs review
2.0
Code