Emacs: Xah JavaScript Mode, xah-js-mode.el
xah-js-mode.el
is a emacs major mode for JavaScript/TypeScript.

This js mode is best if you code pure JavaScript (including ES2015+) and TypeScript. No support for JQuery, React, or any library/frameworks.
Get it by Donation
Goto paypal.com, send $32 to Xah@XahLee.org (be sure to include your correct email address. I need that to send it to you.)
Write in message area: xah-js-mode.el
Features
Syntax Color of All Builtin Words
Colors all JavaScript language builtin object and method names, including ES2015 ones.
Keyword Completion
Keyword completion with ido interface, for ALL builtin words. Press Tab to complete.
Abbreviation for Function/Method Templates
3 hundred abbreviations for templates. For example,
c
→const ▮ = 3
l
→let ▮ = 3
if
→if ( ▮ ) { }
for
→for (let i = 0; i < ▮.length; i++) { }
fo
→for (let p▮ of iterable) { }
fu
→function ▮ () { 3 }
af
→(x▮ => { 3; })
cl
→console.log ( ▮ );
o
→Object.
d
→document.
ogopn
→Object.getOwnPropertyNames ( ▮ )
gebi
→getElementById(▮)
Basically, for most syntax and argument templates for all object methods.