best plugin ever. adds featured image when you embed

For years I have been to lazy to upload an image form y posts that I copy images that are linked as thumbnails, like from picture forums. When you copy and paste the code it doesnt upload amy images to your server so there was never an image to use as featured. Just found this and BAM, every post has a featured image. Wish I found this years ago.

For search- How can I add a featured image from embedded images.