rememberBackdrop can draw a backdrop with custom commands.
Layer backdrop
rememberLayerBackdrop must be used with Modifier.layerBackdrop to draw the Composable's content, or it's derived by using exportedBackdrop parameter of the drawBackdrop modifier. It is coordinates-dependent.
Combined backdrop
rememberCombinedBackdrop can merge multiple backdrops into one backdrop. It is useful to create components such as tabs and sliders.
Canvas backdrop
rememberCanvasBackdrop can draw custom content to a empty backdrop. It is coordinates-independent.