> For the complete documentation index, see [llms.txt](https://docs.thousandeyes.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.thousandeyes.com/product-documentation/browser-synthetics/dual-chromium-option/configure-dual-chromium.md).

# Configuring Dual Chromium

Dual Chromium has settings at both the agent level and the test level. Enterprise Agents must use the **Dual Chromium Version** BrowserBot package to run tests on the newer Chromium track. All Cloud Agents are enabled for Dual Chromium and can run the newer track without additional agent setup.

### Enterprise Agent Settings for Chromium

In **Network & App Synthetics > Agent Settings**, use **BrowserBot Package Type** on the Enterprise Agent **Basic Configuration** tab to control whether an Enterprise Agent can run the newer Chromium track.

The **BrowserBot Package Type** setting has two options:

* **Default**: Runs browser tests on the current production Chromium track. If an Enterprise Agent uses this package type, tests assigned to the agent run on **Default** even when the test setting is **Newer when available**.
* **Dual Chromium Version**: Installs BrowserBot with both Chromium tracks. Tests assigned to the agent can run on the newer track when the test setting is **Newer when available**. Tests that use **Default** continue to run on the current production track.

For more information on agent settings, see [Working with Agent Settings](https://docs.thousandeyes.com/product-documentation/global-vantage-points/working-with-agent-settings).

### Cloud Agent Settings for Chromium

All Cloud Agents are enabled for Dual Chromium. You do not need to configure a BrowserBot package type for Cloud Agents.

### ThousandEyes Validation on Dual Chromium Agents

Before a default Chromium upgrade, ThousandEyes periodically runs automatic validation on tests assigned to agents that can use Dual Chromium, including Cloud Agents and Enterprise Agents with the **Dual Chromium Version** BrowserBot package. These validation runs use instant tests, might appear in your **Activity Log**, and do not consume units.

### Test Settings for Chromium

In **Network & App Synthetics > Test Settings**, use the test-level **Chromium Version** setting to choose whether a page load or transaction test uses the current production Chromium track or the newer validation track.

![Chromium Version setting in transaction test settings](/files/PZAwYMT8mwKZ85okRywk)

For page load and transaction tests, open **Advanced Settings > Browser Options** and set **Chromium Version** to one of the following options:

* **Default**: Runs the test on the current production Chromium track.
* **Newer when available**: Runs the test on the newer Chromium track when the selected agent is a Cloud Agent or the selected Enterprise Agent uses the **Dual Chromium Version** BrowserBot package. If the selected Enterprise Agent does not use the **Dual Chromium Version** package, the test runs on **Default**.

{% hint style="warning" %}
ThousandEyes can update the newer Chromium track as part of the regular browser upgrade process. Chromium changes might affect some browser tests. If a test is critical for production monitoring and has not been validated on the newer track, keep **Chromium Version** set to **Default**.
{% endhint %}