Re-enabling the WGC relay brought back a broken image on the secure->normal
switch. Log root cause: on returning to the normal desktop the relay called
set_advanced_color(target, true) to 'restore HDR', so the rebuilt WGC helper
captured HDR FP16 BT.2020 PQ while the session encoder is 8-bit SDR -> format
mismatch (the 'HDR gets restored when flipping back to WGC' bug).
Gate BOTH set_advanced_color toggles on bit_depth>=10. An SDR (8-bit) session
now stays SDR across WGC<->DDA switches (no HDR force, no needless topology
change); HDR sessions keep the drop-on-secure / restore-on-normal behavior.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
enricobuehler
d2e536d299