Shift+Enter or Ctrl+Enter (depending on the platform) will usually insert a line break. You can divide your greeting from the content of the message without actually sending two messages.
Personally, I don’t care if it’s one message or two. The thing that annoys me is people who send a greeting and then wait for a response before telling me what they actually want. If someone sends “hi” and then immediately starts typing their actual question, that’s fine for me, especially on platforms with a typing indicator.
Shift+Enter or Ctrl+Enter (depending on the platform) will usually insert a line break. You can divide your greeting from the content of the message without actually sending two messages.
Personally, I don’t care if it’s one message or two. The thing that annoys me is people who send a greeting and then wait for a response before telling me what they actually want. If someone sends “hi” and then immediately starts typing their actual question, that’s fine for me, especially on platforms with a typing indicator.