The problem is that if you make a custom module with too light weight, comment.module erase all extra_field.
line 170
<?php
foreach (node_type_get_types() as $type) {
if (variable_get('comment_subject_field_'. $type->type, 1) == 1) {
$return['comment']['comment_node_'. $type->type] = array(
'form'=> array(
'author'=> array(
'label'=> t('Author'),
'description'=> t('Author textfield'),
'weight'=> -2,
),
'subject'=> array(
'label'=> t('Subject'),
'description'=> t('Subject textfield'),
'weight'=> -1,
),
),
);
}
}
?>should by
<?php
foreach (node_type_get_types() as $type) {
if (variable_get('comment_subject_field_'. $type->type, 1) == 1) {
$return['comment']['comment_node_'. $type->type]['form'] ['author']= array(
'label'=> t('Author'),
'description'=> t('Author textfield'),
'weight'=> -2,
);
$return['comment']['comment_node_'. $type->type]['form'] ['subject']= array(
'label'=> t('Subject'),
'description'=> t('Subject textfield'),
'weight'=> -1,
);
}
?>