Anyone can add a picture, gif, video, or share their screen (if there are no restrictions in the room).
Any content that the user has shared will disappear after that user leaves the room. For example, if the user will move to another room or close the browser tab.
To add a picture, gif, or video, and it does not disappear after leaving the room, you need to be an administrator and open the customization menu.
Items added through this menu will not disappear anywhere.