Steam Community :: Guide :: How-To: Play Workshop Coop Maps Solo
Portal 2 Patch Tweaks Co-op, Adds Split-Screen Via Remote Play
9 Awesome Split Screen PC Games for Couch Co-Op Gaming
Portal 2 PC Split-Screen Tutorial with Controller + Keyboard, Mouse - YouTube
Portal 2 Coop Split-Screen - YouTube
Portal 2 on Steam adds split-screen to co-op mode, Big Picture support - Polygon
TIL: Portal 2 does not support UW splitscreen properly :( : r/ultrawidemasterrace
Portal Knights - Vertical split screen is being added to Portal Knights as part of Update v 1.1, coming soon to both PC and console! We know this is a popular request,
8 Best Split Screen games on Steam as of 2023 - Slant
Portal 2 PC - local co-op (splitscreen) gameplay - YouTube
Portal 2 Gets Split-Screen Support in Big Picture Mode | Tom's Hardware
Steam Community :: Guide :: How to play Local Co-op with Controller + Keyboard