I'm working on a Drupal core 6.26 website and I'm unable to debug or find an answer for this problem.
I have a group of users, let's call it GroupTest that has permissions enabled for administer menu.
When trying to edit a menu item or add a menu item with a user from GroupTest group, the add item / edit item form (actually just the fieldset Menu settings) is hidden by an inline "display: none;" style. The only thing visible is the save button.
However, this doesn't happen when I'm using the admin (1) user. The form is displayed just fine.
I've tried different approaches to debug this, looking for hook_form_alter in custom modules/themes that might be modifying this, even for javascript code that would hide the form.
Any help or hint would be greatly appreciated.