OK, thanks for looking into it. My [pull request](https://github.com/dotnet/msbuild/pull/6513) to fix the issue with MSBuild has eventually been merged and it [looks like](https://github.com/dotnet/msbuild/pull/6537) it will be part of VS 16.10.2 (.NET SDK 5.0.302). Hopefully that will be released soon and all will be fine.