HDR editing is switched with an HDR button in the Edit panel header, beside
Auto and B&W and drawn the same way (the shared text_button: highlighted
while on), instead of a checkbox at the top of the Light panel. While HDR is
on, the Light panel still shows Visualize HDR and the headroom slider above
the light sliders; with HDR off they're hidden.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>