Mobile Depth of Field blurry eveywhere

user reports

I investigated the problem throught the frame capture tools and found that on a real device (iPhone 15 Pro in my case), the depth texture for the SunMask pass is not set (a dummy black texture is used instead), resulting in the mask for further blur being fully white.

1. Enable Depth of Field
2. Deploy to iOS device
3. Observe that the scene is blurry everywhere