> For the complete documentation index, see [llms.txt](https://docs.incogniton.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.incogniton.com/extra-features/extension-manager/custom-extensions.md).

# Custom extensions

Add your own Chrome extension to Incogniton from a folder or a .crx file, assign it to profiles, and use it on other computers through cloud saving.

Add a custom extension in **Browser assets > Extensions** with **Add extension**, on the **Custom** tab. You can also add one directly in a profile's editor under **Extensions & Cookies**.

{% embed url="<https://www.youtube.com/watch?v=RDQ4ZBdg3j0>" %}

A custom extension is a Chrome-compatible extension that is not installed from the Chrome Web Store, for example one you built yourself or received as a file. Incogniton accepts it in two forms:

* An extension folder: an unpacked extension. The folder must contain a `manifest.json` file.
* A .crx file: a packed extension. Incogniton unpacks it for you.

{% hint style="info" %}
Custom extensions are a paid feature. On a free plan, adding one in Browser assets shows "Custom extensions are a paid feature", and the **Custom** tab in the profile editor shows "Custom extensions are available on paid plans." Extensions from the Chrome Web Store stay available on every plan.
{% endhint %}

### Add a custom extension in Browser assets

{% stepper %}
{% step %}

#### Open the Add extension window

Click **Browser assets** in the left-side menu and open **Extensions**. Click **Add extension** and switch to the **Custom** tab.
{% endstep %}

{% step %}

#### Choose the extension

Click **Select folder** to pick an unpacked extension folder, or **Select .crx file** to pick a packed extension. If the folder has no `manifest.json`, Incogniton shows "Folder must contain manifest.json". If the same extension is already in your library, it shows "An extension with this file content already exists".
{% endstep %}

{% step %}

#### Name it and add it

The **Extension name** is filled in from the folder name. Change it if you like, add an optional **Description**, and click **Add**.
{% endstep %}
{% endstepper %}

<figure><img src="https://1094567560-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FH8yXxFJjKNEduZ4cdtjg%2Fuploads%2Fgit-blob-510eaaeb811fa38b1e6d3ceb9e6949478d88380f%2FScreenshot%202026-06-18%20120043.png?alt=media" alt="Add extension window, Custom tab"><figcaption></figcaption></figure>

The extension now appears in your extension library. Assign it to profiles as described below.

### Add a custom extension from the profile editor

You can also add a custom extension while you create or edit a profile, without going to Browser assets first.

1. Create a new profile, or open an existing one with **Edit** in its three-dot menu.
2. Click **Advanced** to show all tabs, then open **Extensions & Cookies**.
3. Switch to the **Custom** tab.
4. Enter an **Extension name** and optional **Description**.
5. Click **Select folder** or **Select .crx file** and choose the extension.
6. Click **Add**. The extension is added to your library and assigned to this profile in one go.

To assign a custom extension that is already in your library, tick it under **Custom library** and click **Add selected**.

<figure><img src="https://1094567560-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FH8yXxFJjKNEduZ4cdtjg%2Fuploads%2Fgit-blob-57322620bbf8f8213a262b3cde3369051bd24c5d%2FScreenshot%202026-06-18%20120926.png?alt=media" alt="Profile editor, Extensions &#x26; Cookies tab, Custom library"><figcaption></figcaption></figure>

### Assign a custom extension to one profile

* In the profile editor: open **Extensions & Cookies** > **Custom**, tick the extension under **Custom library** and click **Add selected**.
* From the profile list: open the profile's three-dot menu, click **Extensions**, tick the extension and click **Save**.

### Assign a custom extension to multiple profiles

1. Select the profiles in the profile list.
2. In the bar at the bottom of the list, open the more-actions menu and go to **Browser Management > Add Extensions**.
3. Tick the custom extension and click **Save**.

<figure><img src="https://1094567560-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FH8yXxFJjKNEduZ4cdtjg%2Fuploads%2Fgit-blob-64b072493fde68aa432beac57a95157dbe936055%2FScreenshot%202026-06-18%20121748.png?alt=media" alt="Add extensions to multiple profiles"><figcaption></figcaption></figure>

You can also start from the extension: in **Browser assets > Extensions**, open the extension's menu and choose **Edit Profiles** to pick the profiles that should have it. **Show linked profiles** lists the profiles that already use it.

### Use custom extensions on other computers

When cloud saving is on, a custom extension is stored in the cloud. On another computer where you log in with the same account, the extension shows up in your library. Its files are downloaded automatically the first time you start a profile that uses it on that computer. You don't need to add the extension again.

For this to work:

* Cloud saving must be on (**Settings > Preferences > Enable cloud saving**). With cloud saving off, nothing is downloaded.
* The extension must be stored in the cloud. An extension that was added while cloud saving was off stays on the computer where it was added. To upload it later, turn cloud saving on, open the extension's menu in **Browser assets > Extensions** and choose **Store in cloud**. This option only appears for custom extensions that are not in the cloud yet.

If the files can't be downloaded, the profile still starts, without that extension, and Incogniton shows "Extension files unavailable" with the names of the missing extensions. Start the profile again to retry.

Incogniton only downloads an extension that is missing on the computer. A computer that already has a copy of the extension keeps using that copy.

See [Use profiles on multiple computers](/account-management/cloud-saving/use-profiles-on-multiple-computers.md) for how cloud saving works across computers.

{% hint style="info" %}
If you have any questions about the process or are running into issues assigning extensions, reach out to [Incogniton Support](https://incogniton.com/contact/) for assistance.
{% endhint %}