Camera to RenderTexture alpha not working.

Hi, Im trying to make a shop ui with items (models) rotating. The problem is that the rendertexture alpha always is 1.

No matters what color or alpha is in the camera enviroment or the render texture format.

Also, camera stacking is not working for me, i want to put the objects in front of the UI

Unity version: 2019.3.0f6
URP version: 7.2.0

5861074--623086--upload_2020-5-17_13-57-30.png

Same problem. I am trying to generate previews, but the background is always black and not transparent.

I have confirmed that it is possible with URP of Unity2020.3.23 and Unity2021.2.7.
(1) Set the Render Texture of the Camera to a format with an alpha plane such as R16G16B16A16_FLOAT.
(2) Turn off Post Processing of the Camera.
(3) Alpha plane does not become 1.0.
(4) Implement necessary post processing with Render Features.