Now the colon is gone, because I forgot to add `else { ++ i; }` in my previous comment. Can you amend the PR to


```javascript
  if (url.charAt(0) == '/') {
    var i = baseUrl.indexOf('://');
    if (url.charAt(1) === '/') {
      // absolute path
      i = baseUrl.indexOf('/', i + 3);
    } else {
      // protocol-relative URL
      ++i;
    }
    return baseUrl.substring(0, i) + url;
  } else {
```