I would like to develop a plugin to communicate with Mailchimp. My students are manually enrolled and they have to change their password on their first login. So my idea is to include a checkbox in that page to give them the option to subscribe to our newsletters.
I found that the code which generates that page is in login/change_password.php and login/change_password_form.php. But I don't want to modify any core file of moodle and I don't know where else I should put my code. Could you please give me any idea on where to put it? Thank you in advance.