R4.12 (user report). The copy holding the instance lock opens a local door guarded by a random token in its data folder; a second copy sends its file paths there, lets it take the foreground, and exits 0 instead of showing "already running". Files join the ely_ui::on_open queue every app already uses; the main window comes to the front. Also records the R4.10 round 1 verdict. Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>