Revit Extensions can be added to an existing deployment image from the Deployment section within Autodesk Account.
Example:
Add Revit DB Link 2021 extension to a Revit 2022 deployment image named Revit2022-custom located at D:\deploy\Revit2022.
From the Deployment section in Autodesk Account, Add Revit in the same manner as the original Revit2022-custom deployment image.
Customize Revit and click Specific version, select Revit 2022.
Apply the Customizations in the same manner as the original Revit2022-custom deployment image.
Select the Extensions as in the same manner as the original Revit2022-custom deployment image and add Revit DB Link 2022.
Click Next to move to the Enter Settings step.
Specify the Deployment name and Deployment image path to reflect the original deployment.
Click Next to move to the Create and download step.
Agree to Terms of Use and Click Create.
Run the Deployment download application.
The Autodesk Deployment application will verify if a deployment image exists within D:\deploy\Revit2022 and once detected you will be prompted to either Update the existing deployment or Save in new location. When prompted, choose Update and click Download & update.
Depending upon the amount of difference between the original deployment image and the new deployment configuration, the changes to the deployment image may take a few minutes.
Note: You can confirm that the Revit DB Link 2022 was included in the deployment image by looking at the contents of the setup_ext.xml located in D:\deploy\Revit2022\image\<GUID>\ for reference to Revit DB Link 2022.
WARNING: Any manual changes made to the original deployment image will be lost when the Update is applied to the existing deployment image.