GitZip - Download or create a download link for a GitHub project folder/sub-folder or file.
SEO Analyzer By Neil Patel - A free SEO analyzer for your site
Refined GitHub - Browser extension that makes GitHub cleaner & more powerful
Serpstat - Search analytics, Rank tracking, Backlink analysis and Site Audit tool.
GitHub Hovercard - GitHub Hovercard provides neat hovercards for GitHub.
Serpstat Website SEO Checker - Check your website's SEO, analyze competitors and keywords