I have a code that parses an html page's header looking for ICO images that declared in the following way:

```
<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon">
<link rel="icon" href="/favicon.ico" type="image/x-icon">

```

for example with the code:

```
image = htmlDoc.querySelector('link[rel="shortcut icon"]');
if (image) {
     imageUrl = image.getAttribute('href');
}

```

*(I don't have cross browser issues, because I have an extension's privileges)*

The problem is whenever I go to such sites like <http://www.ebay.com>, or <http://www.amazon.com>, they don't have .ico image in their DOM's header, nevertheless the brand's .ico image is displayed as usual. 

My question is:
Do we have some other ways to attach .ico images beside the way mentioned above or how do they do it?