Two copies opened close together made the second take the first's
launch-pending marker for a crash and switch Window Graphics to OpenGL.
Where OpenGL can't open a window (NVIDIA on X11: "gl not compatible with
provided surface"), every later launch then failed, with no way to reach
the setting.
The marker is now locked while its launch runs, so a locked marker is a
launch still opening, not a crash. And a window that fails to open on
OpenGL puts Window Graphics back to Automatic.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
