Telegram's username field can be empty; here's how to extract the correct handle

Telegram's API can return an empty string for the username field of a chat, even for high-profile accounts like founder Pavel Durov's, because accounts with multiple public handles move them into a separate usernames array. Each entry in that array carries active and editable boolean flags, and only the entry marked both active and editable represents the canonical, owner-controlled handle. Developers who build links using the plain username field or a numeric chat ID risk generating URLs that appear valid but resolve to nothing for users. A three-step fallback function — checking for an active-and-editable handle first, then any active handle, then the plain field — correctly covers both single-handle and multi-handle API response shapes. The issue commonly surfaces when a channel renames itself and retains old aliases, silently emptying the username field without triggering obvious errors.