The docking advanced layout designer is broken when using Visual Studio 2019 Version 16.8.3, some buttons are missing so cannot add ToolWindows etc.
If copying from an old template from net 4.6, the initial docking layout works but dragging a window does not show the dock graphics overlay to dock anywhere.
Essentially docking looks broken on net5.0 (just checked and it's also broken on netcore3.1)