Show print borders

The "Window" > "Show Print Borders" menu shows a yellow and red line around the page (non-printing) showing the print margins and borders. The page boundary is shown by a yellow rectangle and the printing area by a red rectangle. The printing area is determined by the margins on the currently selected printer. Some printers let you adjust the margins, but few let you print right up to the edge of the page.

If any objects on the page lie outside the red rectangle they are unlikely to be printed.