After upgrading to the latest version, davidkingham noticed duplicate icons on the categories page, with one icon appearing on the left and another on the right. The icons had different HTML structures, with the right icon using <svg> and the left icon using <span> with an embedded <svg>. martin suggested that this issue might be related to recent changes that brought category icons into core as a first-class feature, and recommended disabling or removing the Category Icons theme component. davidkingham was able to resolve the issue by setting all category icons and then deleting the component.