I created a Render Texture named it : GUICameraRenderTexture
This is a screenshot of the Player camera : I assigned to the Target Texture the new GUICameraRenderTexture :
Then on the bottom of the hierarchy I have a Main Menu > Camera : The new Camera I changed the Clear Flags to Don't Clear and Culling Mask to Nothing :
Then there is a Canvas the Canvas Render Mode is set to Screen Space - Overlay
And last the Raw Image I assigned to the Texture the GUICameraRenderTexture :
The problem is either in the editor mode or in runtime where the game is running if I disable the new GUI Camera the camera under Main Menu it give error that there is no cameras to render even if the Player camera is enabled.
I want to start the game with the Player camera and then on escape key to switch to the main menu gui camera.
Screenshot if I'm disabling the main menu gui camera :