On his Twitter account, Pavel Durov announced that extended Markdown formatting — tables, headers, formulas, task lists, and expandable quotes — will be available not only for bots, but for regular users as well. According to the founder of the messenger, everything will be tested on bots first:
Planned for later this month, but need to test everything on bots first
You can explore how the formatting works in the interactive demo: @RichTextDemoBot.
#bots