desktop-restore-reuses-framesdesktop-restore-reuses-frames is a variable defined in `
desktop.el'. Its value is
tDocumentation: If t, restoring frames reuses existing frames. If nil, deletes existing frames. If `keep', keeps existing frames and does not reuse them. You can customize this variable. This variable was introduced, or its default value was changed, in version 24.4 of Emacs.