import { DockPanelSvg } from '@jupyterlab/ui-components';
/**
 * A dock panel that freezes heavy panel dimensions during handle drags to
 * reduce layout reflow and improve resize performance.
 */
export declare class OptimizedDockPanelSvg extends DockPanelSvg {
    /**
     * Handle the DOM events for the dock panel.
     *
     * @param event - The DOM event sent to the panel.
     *
     * #### Notes
     * This method implements the DOM `EventListener` interface and is
     * called in response to events registered for the node. It should
     * not be called directly by user code.
     */
    handleEvent(event: Event): void;
    private _isHandlePointerDown;
    /**
     * Whether resize optimizations are enabled.
     *
     * When `true` (the default), panels with heavy DOM content have their
     * dimensions frozen during a handle drag, avoiding repeated reflows.
     * Setting this to `false` immediately unfreezes any frozen panels.
     */
    get optimizeResize(): boolean;
    set optimizeResize(enabled: boolean);
    private _freezeHeavyLeaves;
    private _scheduleRefresh;
    private _refreshFrozenElements;
    private _unfreezeElements;
    private _collectHeavyWidgets;
    private _isDOMHeavy;
    private _optimizeResize;
    private _isResizeDragActive;
    private _frozenGroups;
    private _refreshTimerId;
    private _refreshRAFId;
    private _intervalId;
}