diff --git a/gfx/webrender_bindings/RenderD3D11TextureHost.cpp b/gfx/webrender_bindings/RenderD3D11TextureHost.cpp
index c94692e94e59..fcfe30b7c8b6 100644
--- a/gfx/webrender_bindings/RenderD3D11TextureHost.cpp
+++ b/gfx/webrender_bindings/RenderD3D11TextureHost.cpp
@@ -76,6 +76,10 @@ static bool MapTexture(T* aHost, RenderCompositor* aCompositor,
                        RefPtr<ID3D11DeviceContext>& aDeviceContext,
                        RefPtr<ID3D11Texture2D>& aCpuTexture,
                        D3D11_MAPPED_SUBRESOURCE& aMappedSubresource) {
+  if (!aCompositor) {
+    return false;
+  }
+
   RenderCompositorD3D11SWGL* compositor =
       aCompositor->AsRenderCompositorD3D11SWGL();
   if (!compositor) {