/**
 * One callback observing the viewport visibility of an avatar canvas.
 *
 * @private utility of the avatar rendering system
 */
type AvatarVisibilityListener = (isVisible: boolean) => void;
/**
 * Observes one avatar element and notifies the caller when it enters or leaves the viewport.
 *
 * @param element Observed avatar element.
 * @param avatarVisibilityListener Listener notified with the current visibility state.
 * @returns Cleanup function that stops observing the element.
 *
 * @private utility of the avatar rendering system
 */
export declare function observeAvatarVisibility(element: Element, avatarVisibilityListener: AvatarVisibilityListener): () => void;
export {};