The title of "Course Structure" widget should not be visible

As long as the "Show the Course Overview structure and Preview Options" setting in Course Details is "off", then the actual widget title of "Course Structure" widget, shouldn't be visible.
Please see images:

We were able to surpass this with the following custom CSS code, it should be managed from plugin's code though.

body.single-course .cp_course_strucutre_widget h1.widget-title {
display: none;