Bot API 5.6

• Improved support for protected content: bots can now send it to any chat via the protect_content parameter.
• Implemented spoiler entities both as a new MessageEntity and a supported MarkdownV2 and HTML formatting option.

• See the full changelog for details:

https://core.telegram.org/bots/api-changelog#december-30-2021

Warning: Clients released before December 30, 2021 will display messages containing spoilers as "unsupported message".