History of SyntaxError: "use strict" not allowed in function with "x" parameter Revision history for: English (US) Oct 25, 2016, 10:08:12 AM nbp Add Chrome error message for this error. Previous Oct 25, 2016, 9:43:01 AM arai Oct 25, 2016, 9:42:17 AM arai Bug 1272784 - |function f(a = 1) { "use strict"; }| should throw Early Error.