What is my friend "iPhoneQQ receives offline messages"?

The correct answer to the first question is that he didn't set the background to stay online, and then got off QQ (the avatar is black, and the information card shows that offline messages are accepted. Click to open the dialog box, and the avatar lights up, showing crazy login (as shown in figure 1, figure 2).

If the background online is set (the avatar is lit, the information card shows Crazy QQ online, and clicking dialogue shows that the other party has turned on the offline message push function of Crazy QQ, provided that you can't log in invisibly), as shown in Figure 3 and Figure 4.

The fourth answer is, don't set up a backstage online? Then log in to Crazy QQ and log out.

This is my crazy professional test! ! !