Telegram has a strange behaviour for when it comes to have new lines in the message.
bug that I could reproduce and which is illustrated in the attached
screenshots is when I type new empty lines (screenshot 1*), they get
ignored (screenshot 2). Then when I come back to editing the message
and add new empty lines where I initially wanted to have them
(screenshot 3_) they are not ignored anymore (screenshot 4_*).
Let me know if you need more information.
Thank you for your time!
Telegram Web 1.4.3 K, Firefox 99