Kellen Mace

This plugin adds a play icon to the beginning of the page title whenever an embedded YouTube video is playing. When all videos on the page have stopped playing, the play icon is removed from the page title. This mimics the page title behavior when playing a video on youtube.com. If visitors to your site have several browser tabs open, this is a convenient way they can quickly identify which browser tab contains a web page that is playing video content (making noise).
Also included is the option to display a pause icon in the page title when a video is paused, and the ability to selectively disable the plugin on all pages, all posts, the front page, the home page or on sticky posts, if desired.

YouTube Play Icon

Displays a play icon in the browser tab/title bar when any embedded YouTube video is playing

vuebit

Vuebit automatically creates gif-like previews for every youtube video on your site. It also supports vimeo, dailymotion and streamable embedded videos. This plugin loads vuebit.js in your pages.

Vuebit

Enables gif-like previews for every youtube video on your site.

YouTube Play Icon vs Vuebit