DOF BUG on mobile with 4.19p4

To reproduce this:
1.create a third person template

2.make the post process volume unbound

3.set the dof settings like the screenshot1 below

4.in high-end mobile preview,the dof renders wierd like the screenshot2

If I package this to android mobile(vulkan or es3.1),it will have the same result like PIE.
Please fix this~Thank you very much!

Hello,

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Thanks

Did you find a solution for this? I am also wondering why it has this double screen effect