Lock when the app opens
In the desktop app, go to Settings → Privacy lock. Under "Desktop app only" there's a new option, Lock when the app opens (off by default; set an unlock PIN first):
- Close the app and open it again, and you'll need to unlock before anything shows;
- On Windows, after you close the window to the tray or minimize it, restoring it from the tray or taskbar also asks you to unlock;
- Refreshing the page won't lock it.
Older desktop apps will ask you to update
If you're on an older version of the desktop app, you'll see a prompt in the bottom-right corner to download the new one. Install it once from the download page, and the app keeps itself up to date from then on.