Web version broken in Chrome, Edge

The web version does not generate hashes because of an uncaught javascript error (regression in ebaa224 to fix #13).

Console
```
Uncaught TypeError: Cannot read property 'nodeName' of undefined
    at initForm (browser.js:37)
```

browser.js:37
```
  if (event.originalTarget.nodeName !== "#document") {
    return;
  }
```