When you create a Pull Request, you are actually doing a diff between two branches. It makes sense to get a copy of the diff result for other usage. For example, many teams are trying to do incremental deployment based on the changes in a merge. This extension will help you generate such incremental deployment packages.
Got to VSTS Marketplace and click on install.
Pull Request Diff Copy Exntesion is developed, built and released by Team Foundation Server.