Putting "
" in a text file doesn't make a newline character, it just adds the characters "\" and "n". Hitting return in a textfile is what makes a newline character. That's not a bug or incorrect; in fact it's probably more correct. The string parser in the Unity compiler interprets "
" in strings declared within code as a newline character.
You can just read two lines:
First Line
Second Line
and declare your variable as
string1 = line1 + "
" + line2.
Or you could replace instances of "
" in the string with a newline char.