A very minor tweak suggestion - for those who keep the TOC sidebar very narrow (e.g., when using Joplin in split screen and having 5 columns - notebook list, note list, markdown editor, rendered view, TOC sidebar), small bullet points in front of the TOC headers in various colors (different color for h1, h2, h3, etc.) might make it easier to see at a glance where each header sits in the outline hierarchy. Just a suggestion. Love the this plugin!