Why switching off tonemapper is switching of all effects

As I understand Tonemapping is a process of converting HDR to LDR. Is is good for displaying rendered HDR on monitors. But why switching it off disables all PostProcessing, even bloom, lensflare and scene tint?

I am trying to capture scene 2d to an HDR texture with all postprocessing, so i want to keep HDR information and does not need HDR->LDR on this step. I’ll make it later I think.

Here is my scene and what I get in captured texture.