var test = Array.prototype.shift && Array.prototype.map && Array.prototype.includes && Array.prototype.split;
if ( !Array.prototype.shift ) alert( 'Array.prototype.shift is broken!' );
if ( !Array.prototype.map ) alert( 'Array.prototype.map is broken!' );
if ( !Array.prototype.includes ) alert( 'Array.prototype.includes is broken!' );
if ( !Array.prototype.split ) alert( 'Array.prototype.split is broken!' );
if ( test ) alert( 'Array.prototype seems fine for you.' );