This may have todo something with my installation or system settings, I don’t have another machine to check on. I can open the pipeline tool and click on build rebuild or anything but nothing happens. I thought everything was working, so I uninstaled all previous installations of Visual Studio and I only have Visual Studio 2019 Community right now.
I found this thread here: MonoGame Content Pipeline Tool Doesn't Build XNBs
and I have the same symptoms and the same issue I think…
I changed the preffered language in my system settings and tried again and then when I click on rebuild in the pipeline tool I get an “Choose Just-In-Time Debugger” window. If I cancel it or choose Visual Studio as a debugger and click “continue execution” after that in the new instance of Visual Studio the content gets build.