Steps to reproduce:

1) Disable all add-ons in Firefox
2) Open an URL that points to a XML file
3) AS EXPECTED: A pretty-printed XML is shown
4) Enable the React DevTools Add-on
5) Open the XML file again
6) FAIL: Only the content inside the XML tags are shown

Using Firefox Developer Edition 72.0b6 on macOS 10.15.2
reactBuildType: evt.reactBuildType,
  }, '*');
});
`;
const saveNativeValues = `
window.__REACT_DEVTOOLS_GLOBAL_HOOK__.nativeObjectCreate = Object.create;
window.__REACT_DEVTOOLS_GLOBAL_HOOK__.nativeMap = Map;
window.__REACT_DEVTOOLS_GLOBAL_HOOK__.nativeWeakMap = WeakMap;
window.__REACT_DEVTOOLS_GLOBAL_HOOK__.nativeSet = Set;
`;
if (sessionStorageGetItem(SESSION_STORAGE_RELOAD_AND_PROFILE_KEY) === 'true') {
  const rendererURL = chrome.runtime.getURL('build/renderer.js');
  let rendererCode;
  
  
  
  
  
  const request = new XMLHttpRequest();
  request.addEventListener('load', function() {
    rendererCode = this.responseText;
  });
  request.open('GET', rendererURL, false);
  request.send();
  injectCode(rendererCode);
}
injectCode(
  ';(' + installHook.toString() + '(window))' + saveNativeValues + detectReact,
);