export declare class PreviewError extends Error {
    title: string;
    url?: string;
    fatal?: boolean;
}
export declare class TimeoutError extends Error {
    constructor(what: string, ms: number);
}
export declare class HttpError extends Error {
    readonly status: number;
    readonly statusText: string;
    readonly url: string;
    constructor(url: string, status: number, statusText: string);
}
export declare class WebGLUnavailableError extends PreviewError {
    title: string;
    fatal: boolean;
    constructor();
}
export declare function fetchOrThrow(url: string, init?: RequestInit): Promise<Response>;
export declare function isWebGLError(error: unknown): boolean;
export declare function recordError(error: unknown, url: string): PreviewError;
export declare function referenceError(error: unknown, refType: string, url?: string): PreviewError;