Hello! I am Canadian and I identify as 'queer' and 'gay'. In my culture here, 'queer' is a respectful way to refer to someone who is not straight. Sometimes it is easier to say 'queer' if you do not know the specifics (like if someone is trans, bi, or gay, etc.) I don't think it is offensive at all!

People within that community might use the word among themselves, but it's always best to avoid words that may potentially be offensive. When in doubt, don't use it. By the way, the same word can also mean "strange", "odd" or "unusual", but it's hardly ever used that way anymore.