[Jare]

BASIC had plenty such warts, incompatibilities and lack of 'modern' features. Javascript is still not as immediately available and direct to use as the BASICs of old were. As a beginner, to easily make anything useful and interesting (by today's standards) in Javascript, you need to run it in a browser as a saved file, wrap it in some html, and add a bunch of boilerplate (create a canvas, make stuff move, access the DOM).