GoBouncerBot
  Open bot t.me/gobouncerbot
Attention! To subscribe to «GoBouncerBot» Telegram bot, you must have the Telegram app installed.
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GoBouncerBot — official Telegram bot

Keep your Telegram channel clean by using GoBouncerBot to validate every new user joining your chat. New users have to validate using an captcha to be able to chat within a channel.

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