See the original report in https://github.com/facebook/react/issues/10772#issuecomment-333242375.

The problem is that SVG is case sensitive, and so naïvely setting `tabIndex` and relying on insensitivity won't work with it.

The good news is it seems like `tabindex` is the only valid [SVG attribute](https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute) with this problem. We just missed it because it applies both to HTML and SVG.

I think the fix is to add it back to the whitelist. 
/**
 * Copyright (c) 2013-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @providesModule HTMLDOMPropertyConfig
 */
'use strict';
var DOMProperty = require('DOMProperty');
var MUST_USE_PROPERTY = DOMProperty.injection.MUST_USE_PROPERTY;
var HAS_BOOLEAN_VALUE = DOMProperty.injection.HAS_BOOLEAN_VALUE;
var HAS_NUMERIC_VALUE = DOMProperty.injection.HAS_NUMERIC_VALUE;
var HAS_POSITIVE_NUMERIC_VALUE =
  DOMProperty.injection.HAS_POSITIVE_NUMERIC_VALUE;
var HAS_OVERLOADED_BOOLEAN_VALUE =
  DOMProperty.injection.HAS_OVERLOADED_BOOLEAN_VALUE;
var HAS_STRING_BOOLEAN_VALUE = DOMProperty.injection.HAS_STRING_BOOLEAN_VALUE;
var HTMLDOMPropertyConfig = {
  
  
  
  Properties: {
    allowFullScreen: HAS_BOOLEAN_VALUE,