At first it didn't work on web.telegram.org on PC (tried to download but it said undefined) but I followed a suggestion that I got from googling to change Telegram's mode to K version.
Exact steps are: "To switch to Telegram K from the menu, click the hamburger menu (three horizontal lines) in the top-left corner and select "Switch to K Version" from the dropdown list".
At first it didn't work on web.telegram.org on PC (tried to download but it said undefined) but I followed a suggestion that I got from googling to change Telegram's mode to K version.
Exact steps are: "To switch to Telegram K from the menu, click the hamburger menu (three horizontal lines) in the top-left corner and select "Switch to K Version" from the dropdown list".
Then it started working flawlessly.