AppBar freezes app when Signing the Assembly

When you go into a .NET Core 3.1 WinForms project and check "Sign the assembly" on the Signing tab, and use a self-sign certificate, the AppBar does not work. It blocks all user input and freezes up the app. To resolve, uncheck the box "Sign the assembly". Reproduced on VS2019 16.8.3 , Windows 10 64bit.