Having installed Captcha, I now need to specify on which forms to display the Captcha intervention. There's probably a simple answer, but let this question describe my newb-style ingnorance anyway...

Where can I find a list of existing form names to copy and paste into the Captcha configuration page?

Accepted answer

Tim is almost correct... You'll notice the form ID he mentioned uses hyphens (-), whereas the form IDs required by Captcha and Antibot use underscores (_).

The correct way to find a form ID for use with anti-spam modules is to look for the hidden input element in the form with name 'form_id'. The value of this element is what you want:

Finding form IDs

So in this case (for the comment form at the bottom of this Forum page) the form ID is: comment_node_forum_topic_form

In this case this form ID is different to the ID attribute on the form element itself, but generally they are the same (save for using hyphens vs. underscores).

Comments

Well, there is no single list of forms available, since forms can and are created all the time as you are building your site. I believe that what you are looking for is the `form-id`.

The antibot module (my favorite SPAM prevention module) lists some default forms by default and has a feature that will display the id for all forms on the page during development (you turn this feature off once you are done configuring the module). 

You find the id for a form by looking at the source code and finding the <form> tag and the "id" associated with it. (EDIT: See next post for correction.)

<form class="webform-client-form-6 webform-client-form 
webform-client-form webform-client-form-6" 
action="/contact-us" method="post" id="webform-client-form-6" 
accept-charset="UTF-8">

Here are some default forms that come with Backdrop (as per Antibot module).

user_login
user_login_block
user_pass
user_register_form
contact_site_form

 

See below for screenshot of Antibot module https://backdropcms.org/project/antibot:

 

Tim is almost correct... You'll notice the form ID he mentioned uses hyphens (-), whereas the form IDs required by Captcha and Antibot use underscores (_).

The correct way to find a form ID for use with anti-spam modules is to look for the hidden input element in the form with name 'form_id'. The value of this element is what you want:

Finding form IDs

So in this case (for the comment form at the bottom of this Forum page) the form ID is: comment_node_forum_topic_form

In this case this form ID is different to the ID attribute on the form element itself, but generally they are the same (save for using hyphens vs. underscores).

Thank you, Tim and BW, for your very helpful responses. I am now empowered!

—Eric