jScrollPane
Pretty, customisable, cross browser replacement scrollbars
Cerebral
A state controller with its own debugger
Benchmark.js
A benchmarking library that works on nearly all JavaScript platforms, supports high-resolution timers, and returns statistically significant results. As used on jsPerf.com.
Basket.js
A script and resource loader for caching & loading files with localStorage
Sapphire Db
SapphireDb Server, a self-hosted, easy to use realtime database for Asp.Net Core and EF Core
Rando.js
The world's easiest, most powerful random function.
Custombox
Modal Window Effects with transitions CSS3.
iCheck
Highly customizable checkboxes and radio buttons
Mosaiqy
Mosaiqy it's a jQuery plugin to organize and show image thumbnails and zoom, easy to integrate also with Flickr, Instagram, Panoramio and other. Check carefully the homepage project and source code for full detail, licensing, legal notices and copyright
jQuery QR Code
qrcode generation standalone (doesn't depend on external services)
Tippyjs
Highly customizable vanilla JS tooltip/popover library
Timelined
A customizable CSS-only vertical timeline
Textillate
A simple plugin for CSS3 text animations
Tabletop
Tabletop.js gives spreadsheets legs
Resize Observer
Polyfills the ResizeObserver API.
Officegen
Standalone Office Open XML files (Microsoft Office 2007 and later) generator for Word (docx), PowerPoint (pptx) and Excell (xlsx) in javascript. The output is a stream.
Odometer
Smoothly transitions numbers with ease. #hubspot-open-source