The .NET Framework Version options control settings and CLR version used by .NET actions.
Default .NET Framework Version
Specifies the default .NET Framework version for new .NET actions added to your build. The minimum supported version of the .NET CLR in FinalBuilder actions is .NET 4.0.This is import for .NET SDK, and .NET Client Tool actions as it specifies which version to use tools from.
In addition this option specifies the
Allow reloading of .NET custom action assemblies
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