RemoteApp is basically RDP for one single desktop app running on the remote server but launched and run to appear like a local app. It's improved a lot over the past decade+

There's an extra interesting feature there where the remoteapp windows are aware of each other. It's a niche use case, but the remote side counts as one session, so apps can interact and automation/accessibility mostly works as expected. Although the local system still sees the remote apps as opaque rectangle rather than widgets.