Navigate To Assembly Explorer
Ctrl+Shift+G | Locate in Assembly Explorer
This command helps you examine library types (study their members, base types, inheritors, etc.) using the Assembly Explorer window. The command becomes available when you invoke Navigate to on a library symbol in your source code and on decompiled sources. You can invoke this command from the editor, from the File Structure and other tool windows.
You can also open assemblies in the Assembly Explorer directly from the list of referenced assemblies in the Solution Explorer: