Noted That:

• To install correctly this post-thumbnail-extras.zip.
• Fisrt Download the post-thumbnail-extras.zip to your computer
• Extract/Open post-thumbnail-extras.zip to Your Computer.
• Then, Find readme.txt file inside post-thumbnail-extras.zip and Open readme.txt.
• Now, Read the Requirements of this plugin. Which Wordpress Version and PHP Version are required to run this Plugin in Your Wordpress Site.
• Then, Follow the the Tips Below.

Start the Tips:

1. First Download "post-thumbnail-extras.zip" Plugin to your Local Computer. (Click Download)

2. Then, Login to your "yourdomain.com/wp-admin" Dashboard.

3. Then, Click on "Plugins" + "Add New" from left sidemenu of Dashboard.

4. Now, Click on "Upload Plugin" button.

5. Now, Browse "post-thumbnail-extras.zip" Downloaded plugin from your computer, Where you downloaded post-thumbnail-extras.zip According to Step – 1 Above then, click on "Install Now"

6. Now, Click on "Active Plugin"

7. Then, See left sidemenu. "Post Thumbnail Extras" folder is added on left sidemenu. Now, Click on "Post Thumbnail Extras" folder.

   Noted that: If you do not see "Post Thumbnail Extras" folder on left sidemenu then, see at left sidemenu "Settings" or "Tools".

8. Now you configure yourself oR Watch video tutorial below about Post Thumbnail Extras Configurtions and Settings or How to work "Post Thumbnail Extras" in your WordPress site.

After Activated Plugin According to Step-6 then,

1. Go to "Plugins" + "Installed Plugin" from Wordpress Admin Panel Leftside Menu.
2. or Direct go to: https://yourdomain/wp-admin/plugins.php
3. Then, Find "Post Thumbnail Extras" Activated Plugin from Plugin List.
4. Then, Click on "Settings" from Plugin that is Post Thumbnail Extras
5. Now, Edit/Add/Config the setting and Click on "Save Changes" button,

Shortcode

Use the shortcode [pt] in your posts to quickly embed the featured image as a thumbnail. Use the attribute ‘size’ to change to a different post-thumbnail size (e.g. [pt size='medium']). You can also use any image in your media gallery if you know the id, by using the id attribute ([pt id='100']).

Use the link attribute to wrap the image in a link.

• link='file' will create a link to the full size image.
• link='post' will create a link to the attachment page.
• link='http...' creates a link to any URL.

Use the media library to quickly add this shortcode for the selected image by pressing the “Insert shortcode” button.

Add/Delete Post Thumbnails

1. In Settings ? Media, click the plus sign to add a new post thumbnail.
2. Update the width/height and whether or not the post-thumbnail should be cropped to an exact size. (If the width or height is set to 0, that boundary constraint is not enforced — effectively, it’s infinite). Make sure you click the “save” button so that the changes are stored in the database.