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**Do you want to request a *feature* or report a *bug*?**
A bug

**What is the current behavior?**
When Chrome devtools is highlighting highlight box is shown too small.

![image](https://user-images.githubusercontent.com/44562005/69419027-185ca380-0d5f-11ea-8284-8004147dc713.png)

**What is the expected behavior?**
Highlight box is shown actual template size.

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**
Chrome 78.0.3904.97
React Developer Tools 4.2.0
if (canvas !== null) {
    if (canvas.parentNode != null) {
      canvas.parentNode.removeChild(canvas);
    }
    canvas = null;
  }
}
function initialize(): void {
  canvas = window.document.createElement('canvas');
  canvas.style.cssText = `
    xx-background-color: red;
    xx-opacity: 0.5;
    bottom: 0;
    left: 0;
    pointer-events: none;
    position: fixed;
    right: 0;
    top: 0;
    z-index: 1000000000;
  `;
  const root = window.document.documentElement;
  root.insertBefore(canvas, root.firstChild);
}