WWBN AVideo: Stored XSS via unescaped Gallery category description

WWBN AVideo is an open source video platform. In 29.0 and earlier, AVideo stores category descriptions from user input and later renders category_description as raw HTML in the Gallery view. A user who can create or edit categories can store JavaScript in a category description, which executes when another user views the affected Gallery/category page. This is a stored XSS in the category description field, separate from previously fixed XSS issues in video titles or comments.