When setting the featured image for a post, you usually have to go into each post’s edit screen. Bulk-Select Featured Image is a very useful new plugin that can save you a good number of clicks in this process. It adds an “Use as Featured Image” action to the Media Library.
This can be very useful if you need to set the post thumbnail / featured image for a lot of posts all at once. For example, if you change to a new theme and need to quickly select a bunch of featured images, this plugin will save you quite a bit of time. Download the Bulk-Select Featured Image plugin from the WordPress plugin repository.