Reddit (Au) Comment Highlights is a lightweight, customizable alternative to a feature normally reserved to Reddit gold users. It allows you to highlight unread comments since your last visit to a Reddit comment section. You can add as many user accounts as you wish to your account.

You can even choose which user you want to highlight the unread comments for!

The extension has a clean, lightweight look that doesn't require any permissions and syncs between browser sessions. It is able to work in the background without any impact on the overall performance.

This extension is fully customizable and has no UI.

You can choose the amount of highlighting to show.

The highlighting works as soon as the comment is available.

Other features include:

It works on any site that uses Reddit Enhancement Suite (RES).

It works with Custom CSS.

It is available for the latest versions of Chrome, Firefox, Opera, Safari, and Internet Explorer.

It requires little to no permission.