Hugh Lashbrooke

Sick of adding a image to your post content then also setting it as the featured image in a separate action? Of course you are!
This plugin solves this problem by adding a new button alongside the “Insert into post” button in the media manager modal. When clicked, this button will insert your selected media and then, if you have selected an image, set that image as the post’s featured image.
It is possible to select multiple media items to insert, so this plugin will set the last image in the selected set as the featured image. The button will appear in the media manager modal for all post types.
This plugin works with WordPress 5.0+, but it will only work with Classic block or in the Classic Editor. It does not currently work with the Image block (or any other similar ones).
Want to contribute? <a href="https://github.com/hlashbrooke/Instant-Featured-Image" rel="nofollow ugc">Fork the GitHub repository</a>.
Got some great ideas? <a href="https://wordpress.org/support/plugin/instant-featured-image" rel="ugc">Post on the support forum</a>.

Instant Featured Image

Set an image as the featured image at the same time as you insert it into the post content.

Corey Salzano

This plugin does one thing, and that thing is to add your posts’ featured image to the RSS feed. It specifies the ‘large’ image size.
<h3>Open Graph Meta Tags are also Necessary</h3>
Many modern feed readers do not show the images added by this plugin. Feedly, for example, will not show images added by this plugin. Feed readers crawl article pages to find the image attached to posts in the open graph meta tag. Many SEO plugins add open graph tags for featured images. I like the (https://wordpress.org/plugins/opengraph/)[Open Graph] plugin, too.

Add Featured Image to RSS Feed

Adds the featured image attached to posts to the beginning of the post content and excerpt in RSS feeds.

Instant Featured Image vs Add Featured Image to RSS Feed