Adds the last modified time to the admin interface as well as a [last-modified] shortcode to use on the front-end. Over-powered.
Simple plugin that checks your WordPress install and shows your file permissions, size, and last modified date.
Sends to a client correct HTTP headers Last Modified, Cache Control and 304 Not Modified
Use Post Updated Date Plugin to Add Last Updated Date in WordPress Blog Posts.
This plugins adds the last modified date, current revision and the publication date of your post/page. Simply use the shortcode [last_modified_date]
Automatically send HTTP Header "last-modified".
Correction http headers and disable REST API.
Adds the ETag, Last-Modified, and if appropriate 304 headers to HTTP responses generated by WordPress for more efficient caching.
Add modified date sortable column, featured image custom column to the admin interface for post and pages.
Don’t update a post’s “modified” timestamp for insignificant edits.