achellios

WordPress bloggers will sometimes copy headlines from a WordPress-generated homepage and paste them into the post-editing window. In Firefox, this has the unfortunate result of converting absolute urls into relative ones. For example, copying a headline from http://khaotica.com converts the permalink for this article:
http://khaotica.com/2009/12/firefox-relative-links-fix-wordpress.html
…to a relative link:
../2009/12/firefox-relative-links-fix-wordpress.html
This creates broken links when the post is viewed on the archive page and RSS feed. The links will also be broken for subscribers who receive posts via email.
Enter the Relative Links Fix. This plugin will replace relative urls with the proper absolute urls every time you save or publish a post. If you use WordPress and can’t shake those copy-paste habits, this is the plugin for you.
As always, donations are appreciated. I promise to spend them exclusively on soda (the creative fuel that powers developers everywhere).

Relative Links Fix

Corrects Firefox behavior in which pasting formatted content in the editor converts absolute URLs to relative URLs.

Scott Werner

When inserting an image into a post, WordPress uses absolute URLs to the files. This plugin overrides that functionality and forces it to use relative URLs.
For example:
WordPress Default: 
http://www.example.com/wp-content/uploads/2013/04/example.jpg
Plugin Override: 
/wp-content/uploads/2013/04/example.jpg
This is particularly useful if you plan on switching domains ever as well as reducing HTTP requests.

Relative Image URLs

Creates relative URLs for images when inserting into posts.

Relative Links Fix vs Relative Image URLs