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.

mainsufian

Now its easy to change domains and move your wordpress blog from subdomain to parent domain like from localhost to live domain you just need to use this shortcode [base_url] as your base url and images So now all links and images are fine after transfer site from localhost to live you don’t need to adjust links after change domain.
ShortCode 
[base_url]

Relative URL ShortCode

This Plugin is Best when you need to work on test domain like localhost or on some sub domain and you need to move data or transfer complete site then it's best to keep links fine.



shift content then very useful

Now its easy to change domains and keep links and images fine you just need to use this shortcode [base_url] as your base url for links and images.

Relative Links Fix vs Relative URL ShortCode