# On Firefox

### How to install CSS Pro on Firefox:

To follow these steps, **you need to have purchased a CSS Pro license key**. If you don't have one yet, [**get one here**](https://gum.co/csspro?wanted=true).

{% embed url="<https://www.youtube.com/watch?v=wPaiE5baXxQ>" %}
Video tutorial
{% endembed %}

**Step 1.** **Download the Firefox extension from the link you were redirected** to after buying it or your Gumroad receipt (in your email) or [library](https://gumroad.com/library). If you can't find it, please download the extension via the [My License](https://csspro.com/my-license) page.

**Step 2.** **Drag and drop** the **"Firefox.xpi"** file **into your Firefox** browser window, and click on the button "Add" to install the add-on.

![Click on "Add"](/files/rsvWIaXHvHdw6FDrkGuq)

Now that you have the extension installed, it's time to activate it with a license key, which you've got in your receipt, but can also be retrieved [here](https://cssscanpro.com/my-license) if you forgot/lost it.

**Step 3. You're going to be redirected to a webpage. If that doesn't happen, open any website on a new tab**, for example, Google or your own website.

**Step 4.** **Click on CSS Pro's icon** on your **toolbar** to open the extension:

![](/files/PwYsMijCKOA8qA4I8icF)

A modal (popup) will appear asking for the license.

**Step 5. Input your license key** and validate it by clicking on **"Activate"**:

![](/files/fqtUufqTMf2whS4GQSKq)

🎉 **Done!** Your license is now activated, and you can use CSS Pro anywhere else.‌

The extension will not ask for your license again (unless deactivated or disabled).‌

To manage your license activations in the future, use [the My License page](https://cssscanpro.com/my-license).


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