Incoming Envelope on Telegram

What it signals here

sticker mapping

Corresponds to 'you've got mail' sticker packs; used in channels to alert subscribers to check linked email lists.

channel use

Channel admins use it to preface announcements that are also being sent via newsletter or external email.

group meaning

In group chats, signals that an important document or message has been sent via a linked email or external service.

bot context

Telegram bots use it as an icon for email notification bots or inbox-monitoring services.

See it elsewhere