You can use this post format if you want add video from YouTube to your post.
Post format video – The first <video /> tag in the post will used how featured image for post and on front page too. But you must add the featured image for your post also – this featured image will be used by widgets “Sagablog: Popular posts”, “Sagablog: Popular posts (slider)”, “Sagablog: Recent posts”, “Sagablog: Recent posts (slider)”, “Sagablog: Related posts”, “Sagablog: Related posts (slider)”.
Here you can see how it look like on site:To use this post format you must choose “Format -> Video”:That add YouTube video you must press “Add Media” and choose “Insert From URL”:You can find url for video on youtube.com. You must open page with video and press button “Share”, that you can find under video:Here you can find url that you need:This url must begin from “https://youtu.be/”. And you must insert this url in your site.ATTENTION – do not use caption for image. Image with caption will not be shown.