The Gedit Clientside plugin is now available for Gedit 3. All the features remained the same, just some minor tweaks throughout. You can still find both Gedit versions of the plugin on Github:

I moved the old Gedit 2 version to a separate branch on Github, so both versions of the project are still available.

If you’re unfamiliar with the Clientside plugin you just found a real gem. The plugin bundles together functionality to minify, format, batch minify, and run a lint service on both Javascript and CSS. Hope you enjoy!