# 5. Test Embed Configuration

Before integrating Embed you might want to check that all the settings are correct and the iframe looks as expected for an end user.

### Local testing

In order to open an Embed in a local html page (i.e. where the URL is a file path), you need to specify `file://*` in the **allowed domains**.

### Testing on Google Sites

One can also test embedding the iframe in Google Sites. In order to allow it to open there the **allowed domains** need to be set to: 

```
sites.google.com www.gstatic.com *.googleusercontent.com
```

{% hint style="danger" %}
The **allowed domains** settings above should be used solely during the testing phase, where it's absolutely needed. 

Remove it from the allowed domains once you're going to your staging or production environment as it adds a potential security risk.
{% endhint %}