In what JS engines, specifically, are toLowerCase & toUpperCase locale-sensitive?
Note: Please, note that I couldn’t test it! As per ECMAScript specification: String.prototype.toLowerCase ( ) […] For the purposes of this operation, the 16-bit code units of the Strings are treated as code points in the Unicode Basic Multilingual Plane. Surrogate code points are directly transferred from S to L without any mapping. The result … Read more