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. 
itThrows(
    `when rendering ${desc} with server string render`,
    () => testFn(serverRender),
    partialMessage,
  );
  itThrows(
    `when rendering ${desc} with clean client render`,
    () => testFn(clientCleanRender),
    partialMessage,
  );
  
  
  itThrows(
    `when rendering ${desc} with client render on top of bad server markup`,
    () =>
      testFn((element, warningCount = 0) =>
        clientRenderOnBadMarkup(element, warningCount - 1),
      ),
    partialMessage,
  );
}
async function testMarkupMatch(serverElement, clientElement, shouldMatch) {