One Tuesday, a truly magnificent error appeared: a dialog box that said “Your printer is out of coffee.” Leo knew this was gold. He grabbed his phone, but his hand shook, and the reflection of his face replaced the error text.

Mia later told him about a shortcut: . That saved the picture directly to a folder called “Screenshots,” no Paint required. For a Mac, she said, it was Shift + Command + 3 .

But Leo didn’t want his friends to see his cluttered desktop. He wanted just the error box. So he tried the second trick: . The screen dimmed, and a tiny toolbar appeared at the top. He clicked the rectangle icon, dragged a box around the “out of coffee” message, and let go.

On a Mac, that was , then drag.