Sddm

Problem

After upgrading to FreeBSD 15.1-BETA3 and getting DRM 6.12 working see:freebsd-15.1-drm-i915-runbook.md, Plasma Wayland would not start through SDDM. Logging in via SDDM’s greeter bounced back to the login screen with no error output. wayland-session.log was empty. XFCE (X11) worked fine through SDDM.

Root Cause

Session activation failed in this configuration. ck-list-sessions showed:

$ ck-list-sessions | grep active
        active = FALSE

When a session is not marked active, kwin_wayland cannot acquire DRM device access : /dev/dri/* access fails, libseat/seatd integration may not work, and the Wayland compositor exits immediately, often with no log output. This matches the symptom exactly.

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