In Drupal 8 the module Meta Tag covers the standard cases. The best solution for special elements such as path-based meta tags is the module Context Metadata.
This awesome & practical Drupal 8 SEO book shows you how to optimize your Drupal 8 website for generating traffic, leads, & revenue.
Advanced lossy compression for PNG images that preserves full alpha transparency with TinyPNG.
The Drupal modules bundle copy, node clone and node convert allow you to drastically speed-up your Drupal content management.
Address 80% of the potential for Drupal performance optimization / speed optimization with 3 simple measures.
This howto shows you how you can make the Youtube player responsive. Drupal modules "Media: YouTube" or "Video Embed Field".
Browser Shots is a free and easy to use tool to quickly get a first insight into the browser compatibility of your Drupal website.
Screenfly is a free and easy to use tool to the the responsiveness of your website on all common devices and screen sizes.
Use the modules "Back to Top" or "Scroll to Top" to allow users an easy way to get back on top of a page (scroll to top button/link)
The Drupal "SEO checklist" module verifies your website for proper search engine optimization and helps you to keep track of what has already been done.