Framebuffers are getting freed in the GPUContext base class destructor. But the framebuffer destructors use the MTL/VK/GLContext derived class, whose destructor has already completed at this point. So these contexts are no longer valid to use. Now free the framebuffers earlier. This caused ASAN warnings, it's not known to cause actual bugs. Pull Request: https://projects.blender.org/blender/blender/pulls/132504