X-Plane 12 on Mac mini (M4) via CrossOver: "failed to initialize Vulkan" error

A couple of things jump out from that message

That error text is coming from the Vulkan-to-Metal/OpenGL bridge layer (CrossOver’s translation stack). The key bit is:

An extension required to run the OpenGL bridge is not supported on 2.1 Metal - 90.5

So X-Plane is trying to bring up Vulkan, and the translation layer is saying “I can’t provide a Metal feature/extension this needs right now.” Since you had it running for an hour yesterday, this is usually down to a change in the CrossOver bottle settings, CrossOver version update, macOS update, or a different rendering path getting selected (sometimes after a prefs reset or after installing a plugin/mod).

Step-by-step things to try

1) Grab the exact failure from Log.txt
Before changing too much, open the X-Plane folder and look at:
X-Plane 12/Log.txt
Scroll to the bottom 30–50 lines and see what it says right before the Vulkan failure. That often names the missing extension or shows whether it’s trying a different GPU/adapter path than yesterday.

2) Do a “clean prefs” test (fast and reversible)
Prefs corruption or a rendering toggle can cause X-Plane to pick a different initialization path.

In:
X-Plane 12/Output/preferences/
Temporarily move these out to your Desktop (don’t delete yet):

• X-Plane.prf
• Graphics Settings.prf (if present)
• Control Profiles folder (optional, only if you want a totally clean test)

Then try launching again. If it starts, you can put your control profiles back and re-do graphics settings.

3) Remove 3rd party plugins for the test
Plugins can trigger different rendering hooks, and under CrossOver that can matter.

Temporarily move everything out of:
X-Plane 12/Resources/plugins/
…except whatever is there by default (if you’re not sure what’s default, just move the entire plugins folder to Desktop and let X-Plane recreate it, or create an empty plugins folder and test).

Then run X-Plane again.

4) Verify CrossOver “bottle” didn’t change
If CrossOver updated itself overnight, or if you duplicated/changed the bottle, settings like DXVK/D3DMetal can flip.

I’m not going to guess the exact toggle names since CrossOver UI varies by version, but the goal is:

• Confirm you’re launching X-Plane from the same bottle that worked yesterday.
• Confirm the same graphics translation option is enabled as before (whatever CrossOver uses to translate D3D/Vulkan paths to Metal on your version).

If you did update CrossOver, one practical test is to roll back to the previous CrossOver version that you know worked (or clone the bottle and try different settings in the clone so you don’t break the original).

5) Full restart and check for macOS update side-effects
It sounds basic, but after macOS point updates, I’ve seen Metal initialization behave differently until after a full reboot. So: reboot the Mac mini, then try again once with no other 3D apps open.

A reality check (important)
X-Plane 12 is native on macOS and uses Metal directly. Running it via CrossOver adds an extra translation layer that can break when either side updates (macOS/Metal, CrossOver, bottle config, etc.). If you have the option, the “stable fix” is almost always: run the native macOS X-Plane 12 build rather than the Windows build through CrossOver.

A few quick questions so I can narrow this down

• Which exact X-Plane 12 build are you running (12.xx and whether it’s Steam or Laminar installer)?
• Did CrossOver update (or did macOS update) between “worked for an hour” and “now fails”?
• Can you paste the last ~40 lines of Log.txt (from the first run that fails)?
• Any addons installed since yesterday (plugins, Lua scripts, reshade-type tools, aircraft that ship plugins)?