A well designed vanilla JS resource:
☝️ Can search via method name or the task you want to accomplish.
A great list of commonly used native JS methods and API's:
https://vanillajstoolkit.com/reference/
☝️ Stuff like DOM Injection, DOM Traversal, JSON, AJAX, and array API's
Accomplish common tasks with native JS:
☝️ DOM manipulation, handling events, organized by task instead of API
Some fancy JS snippets for very specific tasks
https://www.30secondsofcode.org/js/p/1/
A great list / 1:1 breakdown of jQuery Methods and what their modern API's look like:
https://github.com/nefe/You-Dont-Need-jQuery
These folks really broke it down well. Seems up to date too.
The ever classic:
youmightnotneedjquery.com (Github)
and...
youmightnotneedjqueryplugins.com (Github)
In blog format by Tobias Ahlin:
https://tobiasahlin.com/blog/move-from-jquery-to-vanilla-javascript/
Vanilla JS Doc Ready function:
IE9+ (most simple) https://stackoverflow.com/a/31171096/908059
☝️ Browser support: https://caniuse.com/#feat=domcontentloaded
NOTE: Some people want to if/else if DOMContentLoaded has already been completed. ¯_(ツ)_/¯
OR (mini function): https://stackoverflow.com/a/30757781/908059
OR IE6+ (full fleged function): https://github.com/jfriend00/docReady