回复主题（私信）时，标记在发件人标题中

[angus (Angus McLeod)]

If you’re an admin here on meta you can see a live example in the PM where the screenshot was taken.

[Don]

Hello,

I can confirm but actually this is also happens if I reply to the OP.

[pmusaraj (Penar Musaraj)]

Thanks @angus @Don, we will fix this shortly.

[blake (Blake Erickson)]

This has been fixed here on meta.