After successfully activating the plugin go to your post list or product list page and hover any product you can see two additional icons.
The first icon is to change and upload the thumbnail of the featured image. Click on the icon and a media popup window will open up from there you can choose images from your media library. There is no need to open up the post or product page. There is also no limit you can change unlimited thumbnails with this plugin.
There is also a delete icon available. So if you want to delete the thumbnail of any post just click on the icon. It will delete the thumbnail of that specific post.
If there is no thumbnail in any post or product you can see the plus icon when you hover to the product. Click on the plus icon and then upload or select your images.
That’s it! no edit page is required to change the thumbnail.