The Mononote plugin ensures that each note is opened in only one tab per window pane in Obsidian. When a note is already open, the plugin focuses on its existing tab rather than opening the same file in a new tab. This functionality works seamlessly for notes accessed via links, menus, or hotkeys. To function correctly, users must enable the 'Always focus new tabs' option in the Editor settings. Mononote helps streamline workflows by minimizing duplicate tabs, offering a more organized and efficient note-taking experience.