If something asks an overly long password question then Plymouth does not break the line and does not show it aligned to the center of the screen. Instead it shows it starting left-aligned with the password box and then going all over to the right of the screen. Plymouth should ideally break lines, but at least center questions on the screen.

You can easily reproduce this issue by booting a currenty F15 systemd system with an encrypted harddisk on a medium or small sized screen.