Sure, I can help you with that! To enable the dark theme in Azure DevOps, follow these steps:

1. Sign in to Azure DevOps: Go to the Azure DevOps portal and sign in to your account.

2. Access User Settings: Once you’re signed in, click on your profile picture or display name in the top-right corner of the screen. This will open a dropdown menu.

3. Select Personal Settings: From the dropdown menu, select “Personal settings.” This will take you to your personal settings page.

4. Choose Theme: On the personal settings page, you should see an option to choose your theme. Select “Dark” from the available themes.

5. Save Changes: After selecting the dark theme, make sure to save your changes. There should be a “Save” or “Apply” button at the bottom of the settings page.