--- a/dom/canvas/WebGLContextGL.cpp
+++ b/dom/canvas/WebGLContextGL.cpp
@@ -1237,17 +1237,18 @@ WebGLContext::DoReadPixelsAndConvert(con
     if (gl->WorkAroundDriverBugs() &&
         gl->IsANGLE() &&
         gl->Version() < 300 && // ANGLE ES2 doesn't support HALF_FLOAT reads properly.
         IsNeedsANGLEWorkAround(srcFormat))
     {
         MOZ_RELEASE_ASSERT(!IsWebGL2()); // No SKIP_PIXELS, etc.
         MOZ_ASSERT(!mBoundPixelPackBuffer); // Let's be real clear.
 
-        const GLenum readType = LOCAL_GL_HALF_FLOAT_OES;
+        // You'd think ANGLE would want HALF_FLOAT_OES, but it rejects that.
+        const GLenum readType = LOCAL_GL_HALF_FLOAT;
 
         const char funcName[] = "readPixels";
         const auto readBytesPerPixel = webgl::BytesPerPixel({format, readType});
         const auto destBytesPerPixel = webgl::BytesPerPixel({format, destType});
 
         uint32_t readStride;
         uint32_t readByteCount;
         uint32_t destStride;