A method, structure, and method of design relating an electrical structure that includes a metal voltage plane laminated to a dielectric substrate. A determination is made as to where to place an opening for venting gases generated during fabrication of the dielectric laminate. An identification is made of a problematic opening in the metal voltage plane that is above or below a corresponding metal signal line within the dielectric laminate, such that an image of a portion of the corresponding metal signal line projects across the problematic opening. An electrically conductive strip is positioned across the problematic opening, such that the strip includes the image. In fabrication, the dielectric substrate having the metal signal line therein is provided. The metal voltage plane is laminated to the dielectric substrate. The opening in the metal voltage plane is formed such that the strip is across the opening and includes the image.