Tag Snag от Maxwell Pepper

This extension is great for SEO, and will help you find popular relevant tags for your YouTube videos.

Features:

★ Single Mode - Navigate to a single YouTube video and grab all of the video tags.

★ Multiple Mode - Search a keyword on YouTube and grab all of the video tags for the top 10 videos.

★ Easily copy all of the tags to your clipboard and start implementing them into your own videos