WP Set Featured Image From Content
by Mark Jansen on WordPress.org

The Settings screen.
Get the first image from the content of a post and set that image as a featured image.
Features
- Select the (custom) post type for which you want to set the featured images
- Ability to overwrite existing featured images.
Active installations20+
Weekly downloads
12+20.00%
Version1.0.3
Last updated11/18/2016
WordPress version3.0
Tested up to4.5.32
Tags
featured imagepost thumbnails