You will just need to the URL of the image and that will help you to save the image in your WordPress media library and set it as featured image for your post... Here in this post we have collected some of the best image thumbnail plugins for WordPress which will take care of all the aspects related to your featured image thumbnail and make your site look attractive and professional.. Also when you change the theme of your site you will have to regenerate the thumbnail sizes because the image sizes are different for different themes and your old image size may not fit perfectly with the new design.. It's a must use plugin right after you change your theme once you install a new theme you should install this plugin and regenerate all the image again to fit perfectly in the new theme... This plugin offers you to manage and edit your images perfectly this plugin attempts to give the users an interface to manually fix those thumbnail and random images...
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