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### Issue Details
Electron Version: All Version
Operating System: macOS 10.15.3
Last Known Working Electron version: Never

### Bug
The color picker in devtools does not work.
In devtools if you want to change the colors of the CSS code. When you click on a color a color picker is supposed to appear but it does not appear.

### Screenshots
<img width="1013" alt="Capture d’écran 2020-09-07 à 11 42 44" src="https://user-images.githubusercontent.com/70572698/92374841-988ea280-f100-11ea-96be-afc93f6dd645.png">

shell/browser/ui/inspectable_web_contents.cc
public:
    network::mojom::URLLoaderFactory* get() {
      return ptr_.get() ? ptr_.get() : refptr_.get();
    }
    void operator=(std::unique_ptr<network::mojom::URLLoaderFactory>&& ptr) {
      ptr_ = std::move(ptr);
    }
    void operator=(scoped_refptr<network::SharedURLLoaderFactory>&& refptr) {
      refptr_ = std::move(refptr);
    }
   private:
    std::unique_ptr<network::mojom::URLLoaderFactory> ptr_;
    scoped_refptr<network::SharedURLLoaderFactory> refptr_;
  };
  static void Create(int stream_id,
                     InspectableWebContents* bindings,
                     const network::ResourceRequest& resource_request,
                     const net::NetworkTrafficAnnotationTag& traffic_annotation,
                     URLLoaderFactoryHolder url_loader_factory,
                     DispatchCallback callback,
                     base::TimeDelta retry_delay = base::TimeDelta()) {
    auto resource_loader =
        std::make_unique<InspectableWebContents::NetworkResourceLoader>(
            stream_id, bindings, resource_request, traffic_annotation,
            std::move(url_loader_factory), std::move(callback), retry_delay);
    bindings->loaders_.insert(std::move(resource_loader));
  }
  NetworkResourceLoader(