Thank you! Lifesaver!
Anyone has a clue which element this is? It is placed over my div.list-controls and is called either ember27, ember28, main-container or container from my very amateurish (yep i deserve that) eye to read code.
The line I am trying to remove is placed within the blue lines on this photo:
And thank you to @RGJ and @merefield for your support and saving my day.