X-Plane 11.11 is a minor update that addresses stability issues with AMD graphics cards.
11.11 has been in Beta for the last week, and is now available for everyone on Steam. If you don't get the update immediately, re-start your Steam client.
This update fixes crashing with certain AMD GPU/driver combinations a few other stability problems.
See the Release Notes for a full list of changes.
The next Beta will contain full SteamVR support and is due to start very soon now.