I am using th WPJobManager plugin and i want to add un custom field in their job submit form.
I have read this article(https://wpjobmanager.com/customization-snippets/#removeField) and it really helped me for some customisation but i don’t find out how to add my own field. The form file is class-wp-job-manager-form-submit-job.php (location: plugins/wp-job-manager/includes/forms/).

How can i do it please ?