Customize default Prompt options (camera to share) when I trigger camera in Firefox with code development

I am having 2 cameras in my PC. When I try to trigger camera in firefox it always opens a permission prompt box with a webcam options. But I don’t want to show the camera options in the prompt box. So Is there any customizable thingy to customize the Prompt box for firefox by updated any javascript changes (I am a developer. So want to fix it by code updation itself for my web application) Anyone please help me resolve this problem ?