/**
 * Browser extension injection support.
 *
 * Chrome extensions require a persistent profile directory — incompatible
 * with headless Docker by default. This module handles:
 *   1. Persistent profile directory per extension set
 *   2. Extension download from .crx URL or load from local path
 *   3. Launch args for Playwright / Stagehand
 *
 * Usage:
 *   const profile = await prepareExtensionProfile(['/path/to/ext.crx']);
 *   // pass profile.userDataDir and profile.args to browser launch
 */
export interface ExtensionSource {
    /** Local .crx file path or https:// URL to download from */
    source: string;
    /** Friendly name for logging */
    name?: string;
}
export interface ExtensionProfile {
    /** Chrome user-data-dir containing Preferences + extension unpacked dirs */
    userDataDir: string;
    /** Args to append to chromium launch — includes --load-extension and --disable-extensions-except */
    args: string[];
    /** Cleanup the profile directory when done */
    cleanup: () => Promise<void>;
}
/**
 * Prepare a Chrome user-data-dir with the given extensions loaded.
 * Returns profile info + cleanup function.
 */
export declare function prepareExtensionProfile(extensions: ExtensionSource[]): Promise<ExtensionProfile>;
/**
 * Ad-blocker extension profile using the uBlock Origin CRX.
 * Reduces noise from ad networks during crawls.
 */
export declare function adBlockerProfile(): Promise<ExtensionProfile>;