Bot API 6.1

Media in Descriptions

Added support for photos and videos in the 'What can this bot do?' section (shown on the bot's start screen). Use BotFather to set up media.

Added the fields version, headerColor, backgroundColor, BackButton, HapticFeedback and the methods isVersionAtLeast, setHeaderColor, setBackgroundColor, openLink, openTelegramLink, openInvoice to the class WebApp.
Added the field secondary_bg_color to the class ThemeParams.
Added the method offClick to the class MainButton.
Added the fields chat, can_send_after to the class WebAppInitData.
Added the events backButtonClicked, settingsButtonClicked, invoiceClosed.

Added the fields join_to_send_messages and join_by_request to the class Chat.
Added the ability to process join requests which were created without an invite link. Bots will receive a “chat_join_request” update as usual.
Added the method createInvoiceLink to generate an HTTP link for an invoice.

The maximum value of the field file_size in the classes Animation, Audio, Document, Video, Voice, and File can no longer be stored in a signed 32-bit integer type. This change is necessary to support 4GB files uploaded by premium accounts.
Added the field is_premium to the class User.
Added the field premium_animation to the class Sticker.

Added the field added_to_attachment_menu to the class User.
Bots integrated in the attachment menu can now be used in groups, supergroups and channels.
Added support for t.me links that can be used to select the chat in which the attachment menu with the bot will be opened.

Added the parameter secret_token to the method setWebhook.
As previously announced, only HTTPS links are now allowed in login_url inline keyboard buttons.