The "Run" panel does not print empty lines, sometimes.

I have a console app which prints to console.

Console.WriteLine("a");
Console.WriteLine();
Console.WriteLine("b");

When I run it with the "Use external console" option checked, the output in the system console is always:

a

b

When I run it (for the first time after opening the app) without the external console checked, the output in the "Run" panel is the same:

a

b

However, when I run it for the second time or any subsequent time, the output in the "Run" panel is:

a
b

The difference is that there is no empty line after "a". So the behavior of the "Run" panel is inconsistent, depending whether the app is run for the first time or not.