Maybe they used ReSharper ? ReSharper Intellisense is definitely nicer than Visual Studio - among other things, when it shows overloads, it shows several at a time - I can never stand the way Visual Studio does this ...
I just checked and I do not believe that ReSharper does this by default, but there is an option in ReSharper / Options / Environment / Intellisense / Completion Appearance: "Show membership signatures." Enabling this option gives the desired options.
I don't think vanilla Visual Studio has an equivalent option.
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