WebStorm supports that, too, and even adds debugging support for source maps to trace TypeScript, CoffeeScript, or ECMAScript 6 code transpiled to JavaScript. Code inspections built into WebStorm ...

Most source code files hosted on GitHub are actually clones of previously created files, ... or approximately 17.63% of all the analyzed files. JavaScript projects contained the most duplicate files.

Additionally for JavaScript, Microsoft has aligned the semantic highlighting of JavaScript source in HTML files with what is seen in normal .jscode files. This makes code colors more consistent ...