Don't show Lettera folder when I launch the app by opening a file

I’m mostly using Lettera right now to work on one-off markdown files rather than the folder structure sidebar. But every time I open a file and it launches the app (the app was not already open) it keeps opening both the file I double-clicked, and another window with the Lettera folder with it’s default “Welcome to Lettera” document in the sidebar.

Is there any way to get it to stop doing that? I didn’t want to delete that folder as I had wanted to keep that document around for reference, but maybe that would fix it.

If all windows of Lettera are closed but the app is still active then this doesn’t occur. In order to let it happen, Lettera itself as app must be quitted. If so, then the iCloud folder always opens even if it was closed before quitting. Seems to be a bug?