/**
 * Validates that an externally-sourced image URL is safe to render as an
 * `<img src>`. Token icon URLs come from the MoonPay currencies API response,
 * so they are treated as untrusted input: only absolute HTTPS URLs are allowed,
 * which rules out `javascript:`, `data:`, and other non-network schemes.
 */
export declare const isTrustedImageUrl: (url: string | undefined) => url is string;