As said in another post, yes, in reality at today it seems we can have that at least two different ways, despite it seems they work to user and not to groups, in the kind of:

either tg://resolve?domain=username&text=hello+there

or https://t.me/username?text=hello+again

that will open on the telegram desktop the chat to the given user with the text message compiled, but it still needs the manual entry of the send message bar by pressing enter button. Is there any way to escape the need for this, by passing some other specific token to the browser address or some settings on the browser or telegram desktop app?

Or alternatively there is a way to send message and confirm sending in telegram web by adding not only th euser/group but also the message text in the browser address bar?