A workaround for "full" .NET Framework targets to try to fallback on Mono before failing

dotnet-fall-back-on-mono.csproj

<Project Sdk="Microsoft.NET.Sdk">

    <PropertyGroup>
        <TargetFrameworks>netstandard2.0;net40;net45;net471</TargetFrameworks>
    </PropertyGroup>

    <!-- A workaround for "full" .NET Framework targets to try to fallback on Mono before failing -->
    <PropertyGroup Condition="'$(OS)' != 'Windows_NT' And $(TargetFramework.StartsWith('net'))">
        <!-- Look up for Mono installations on Linux or macOS -->
        <MonoPath Condition="'$(MonoPath)' == '' And Exists('/usr/lib/mono')">/usr/lib/mono</MonoPath>
        <MonoPath Condition="'$(MonoPath)' == '' And Exists('/Library/Frameworks/Mono.framework/Versions/Current/lib/mono')">/Library/Frameworks/Mono.framework/Versions/Current/lib/mono</MonoPath>
        <!-- Try to apply framework override fo supported targets if Mono was found -->
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And ('$(TargetFramework)' == 'net20' Or '$(TargetFramework)' == 'net35')">$(MonoPath)/2.0-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net40'">$(MonoPath)/4.0-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net45'">$(MonoPath)/4.5-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net451'">$(MonoPath)/4.5.1-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net452'">$(MonoPath)/4.5.2-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net46'">$(MonoPath)/4.6-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net461'">$(MonoPath)/4.6.1-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net462'">$(MonoPath)/4.6.2-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net47'">$(MonoPath)/4.7-api</FrameworkPathOverride>
        <FrameworkPathOverride Condition="'$(MonoPath)' != '' And '$(TargetFramework)' == 'net471'">$(MonoPath)/4.7.1-api</FrameworkPathOverride>
    </PropertyGroup>
        
</Project>