ICQ 8

As soon as someone writes you a message in ICQ, instead of a status icon, a small flashing envelope will appear near the clock .

Point the mouse at the envelope — you can see who sent the message in the tooltip that appears,  as well as the beginning of the message, if you have enabled the corresponding option in the settings.

Click on the tooltip that appears with the left mouse button — a conversation window opens, in which you can read the message from your conversation partner and continue the discussion, if necessary.