Readme file contain instruction suitable for Azure DevOps Services and Azure DevOps Server with inherited model
But it does not cover "On premise XML" model:
https://learn.microsoft.com/en-us/azure/devops/reference/on-premises-xml-process-model?view=azure-devops-2022&viewFallbackFrom=azure-devops
Would be good to cover it as well (describe how to add/button configure control in case of "On premise XML" model)