Powershell tools WPF older versions XAML vs code

A few years back I developed a WPF based PowerShell app that is used to process paper mailouts a couple of times a year. The PC that I developed it on died a month or so back. Since I created that App I have been working mainly on Linux, so my recollection as to how I put the app together is a bit hazy (yeah I know … keep notes!) So I created a new setup (based on Windows 11 rather than 10 for ease of new motherboard support) Firstly Visual Studio with tools won’t open the project. It says the project is incompatible


On inspecting the various .ps1 files in the project there is a RTMinvocing.designer.ps1 file and this contains ps code to create all the WPF objects. So my (stupid) question is did I even create this with PS tools? Looking at the way it works now the designer creates a XAML file and then sucks it in. Did the WPF element of PS Pro tools work differently a few years back or did I use some other tool to create this app? I do vaguely remember playing around following some articles creating a XAML file in the C# project designer and copying it as a string into a test PS app , then I discovered a tool that would make life easier which I thought was PS Pro tools.