The Sidebar Expand on Hover plugin enhances the usability of Obsidian’s sidebars by enabling automatic expansion when hovering over ribbons. Users can pin or unpin the sidebar state by double-clicking on the ribbons and customize sidebar width either by dragging or through settings. The plugin remembers the previous state of the sidebars upon relaunch, ensuring a seamless experience. This feature simplifies navigation and improves workflow efficiency by making sidebars more accessible.