Tabs and panes let you work in more than one document at a time, but both of them live inside a single RemNote window, so they can only ever divide up the space that one window occupies. If you have a second monitor, or simply a large one, that leaves a lot of room unused, and it means a PDF and the notes you're taking on it have to share the same rectangle.

The desktop app can open several windows at once, which solves this. You might keep a lecture PDF filling your external monitor while your notes stay on your laptop screen, or practice flashcards in one window while you look something up in another, without switching back and forth between them.

Press Ctrl+Shift+N (Cmd+Shift+N on a Mac).

You can also open a window from a menu, though the menu differs by platform. On Windows, press Alt to bring up the menu bar, then choose File > New Window.

On a Mac, right-click the RemNote icon in your Dock and choose New Window.

Each window is a complete copy of the app, with its own sidebar, and pane layout, so you can arrange each one however that piece of work needs. They're all looking at the same knowledge base, which means an edit you make in one window appears in the other, and a flashcard you practice in one won't come back around in the other.

Windows behave like any other window on your computer: drag one to a second monitor, resize it, or put two side by side using your operating system's own snapping shortcuts. Closing a window closes just that window and leaves the rest of your work untouched.