Update support.md a bit.

Bug: None
Change-Id: I7c834a97aea19f9643a7cc2bc0b91e52cbd81fae
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/185184
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/docs/support.md b/docs/support.md
index 99bc0c4..5ce02f6 100644
--- a/docs/support.md
+++ b/docs/support.md
@@ -6,7 +6,7 @@
 Vulkan is the preferred target API on platforms that don't have other "modern" GPU APIs.
 Vulkan is supported as best effort on other platforms (e.g. Windows and macOS).
 
-**Required version**: Vulkan 1.0 is supported with some required extensions (`VK_KHR_maintenance1`), or Vulkan 1.1 and above without extensions.
+**Required version**: Vulkan 1.1.
 
 **Required features**: `depthBiasClamp`, `fragmentStoresAndAtomics`, `fullDrawIndexUint32`, `imageCubeArray`, `independentBlend`, `sampleRateShading`, and either `textureCompressionBC` or both of `textureCompressionETC` and `textureCompressionASTC_LDR`.
 
@@ -38,7 +38,7 @@
 
 **Apple OS support:**
 
- - macOS: supported.
+ - macOS: supported on version 10.15 and above.
  - iOS: supported, best effort.
  - tvOS/ipadOS/...: Not supported, contributions welcome.
 
@@ -47,8 +47,6 @@
 Support for OpenGL is in progress with the aim to make OpenGL ES 3.1 (with extensions and limits) supported through EGL.
 Other flavors of OpenGL (desktop OpenGL) or binding APIs (GLX, WGL, EAGL, CGL) are supported as best effort with contributions welcome.
 
-
 ## Microsoft's D3D11
 
-Dawn doesn't have a D3D11 backend at the moment, but D3D11 support can be achieved with the OpenGL ES backend through ANGLE's OpenGL ES to D3D11 translation.
-There might be a D3D11 backend in the future.
+A work-in-progress D3D11 backend is available but not considered ready for production uses yet.