When I do a tweet starting by @AnotherUser like this:
@AnotherUser Hello I would like to tell you that ...
will the tweet appear in the timeline of my followers?
If so, it would be annoying because the goal is to do a "Direct message" to someone. (Why don't I do a Direct message? Because you cannot do a direct message to someone who doesn't follow you.)
Best Answer
Assuming it's a new tweet, your followers and the followers of the person you're mentioning will see it.
If it's an actual reply, only those people who follow you and that person you're replying to will see it.
A note: You can direct message someone who doesn't follow you if they've turned on the "Anyone Can send messages" feature.
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