Tabs and windows
Several documents at once, in tabs or in separate windows, and the small things tabs do that are easy to miss.
Every document opens in a tab. Each tab is saved on its own and keeps its own backups, so you can keep several pieces open at once without any of them getting in the way of the others.

Opening and closing
+ at the end of the strip, or Ctrl+N⌘N, opens a new empty tab. Opening a file from disk opens it in a new tab too, unless the current one is empty, in which case it is reused.
To close a tab, hover over it and click the × that replaces the unsaved dot. The middle mouse button also closes a tab on Windows and Linux; on a Mac, ⌘W closes the current one. Closing a tab with unsaved changes asks whether to save them. If you choose to close without saving, the document is not lost: it goes to the trash of closed documents, where it stays for 15 days. See Backups and previous versions.
A document with unsaved changes shows a dot on its tab.
Moving between tabs
Ctrl+Tab⌥⌘→ goes to the next tab and Ctrl+Shift+Tab⌥⌘← to the previous one. On a Mac these are in the View menu as well.
Drag a tab to reorder it. On a touch screen, drag with a finger, no long press needed.
When the tabs do not fit
When there are more tabs than the strip can show, the ones that do not fit are grouped under a … button at the end of the strip, which lists them. If you would rather have them all in the strip, narrow as they get, turn off .
Windows
On Windows, Mac and Linux you can open a second window from the main menu, New window, and put it on another screen or next to the first. Each window has its own tabs. Settings apply to every window at once.
Only one copy of the app runs at a time: opening a file from the system while Calmly Writer is already running opens it as a tab in the window you used last, and launching the app again with no file opens a new window. When you quit and come back, the first window reopens the tabs it had, in the same order.
More in Getting started
Where to get Calmly Writer for each system, what the installer registers, and how updates arrive without you doing anything.
The 14-day trial of the desktop app, how a license key works, and what is different about buying the Android app.
What is on the screen when you open Calmly Writer, and where the rest hides until you need it.
Calmly Writer