babel/packages/babel-plugin-proposal-json-strings/test/fixtures/json-strings/directive-line-separator/output.js

"before\u2028after"; //     ^ That's a U+2028 LINE SEPARATOR UTF-16 char (between 'before' and 'after')

"\u2028"; // Just a U+2028 LINE SEPARATOR

"\
"; // Escaped U+2028 LINE SEPARATOR

"\u2028"; // Escaped U+2028 LINE SEPARATOR