title: Mixing .NET 3.5 with 4/4.5 assemblies in the same process
body: <p>I'd like to migrate a .NET 3.5 WinForms based application to the latest .NET version (4.5).</p>
  
  <p>The application uses "external" components (can be thought of as plugins) that are also currently .NET 3.5 based.</p>
  
  <p>I'd like to know what runtime/core libraries are used in case we convert <strong>ONLY THE APPLICATION</strong> to compile using .NET 4.5?</p>
  
  <p>Should this scenario properly work? (loading .NET 3.5 assemblies in a 4.5 process)?
  * The plugin assemblies are loaded via reflection. </p>
  
  <p>How does the CLR runtime handle such a scenario? is this a safe practice?</p>