How to use post process material on camera with a post process volume effect too?

Hello !

I am currently using a post process material on my camera to create a black background (because I am building an application for Hologram and a black background is needed) but I am also using a post process material on my post process volume to create an highlight on object with “Render CustomDepth Pass” selected. The problem is, because of the post process material on my post process volume, my post process material on my camera don’t work anymore.
I try to play with priority or blend weight but nothing seems to work.
Is there a way to make it both work together ?

Thank you in advance !