Libsass Autoprefixer Warnings from SCSS

With the latest version of CodeKit App, using Libsass 3.6.4 I am seeing warnings that seem to be coming from compiled CSS, from the Foundation sites scss.
This is on foundation-sites v6.6.3

#menuLayer.menuOpen .mainNav .beforeMenu, #menuLayer.menuOpen .mainNav .mainNav, #menuLayer.menuOpen .mainNav .afterMenu, #menuLayer.menuOpen .mainNav .socialNav { display: contents; width: 100%; padding: 0 0.5rem; }

Gives the following:
autoprefixer: COMPILED CSS FILE style.css:2176:165: Please do not use display: contents; if you have grid setting enabled

.gallery { margin-bottom: 1.5em; display: -ms-grid; display: grid; grid-gap: 1.5em; }

Gives the following:
autoprefixer: COMPILED CSS FILE style.css:311:49: grid-gap only works if grid-template(-areas) is being used

Is anyone else getting similar?