A. Description

It is possible that the titles of chapter or sections will occupy more than the width of a single line. When this variable is empty, headers will be allowed to occupy multiple lines. However, it is possible that the left-hand portion of a header will collide with the right-hand portion of header. To prevent this, headers can be truncated if they exceed an allowable width. When this variables is set to a number from zero to 100, the left-hand (or inside) side of each header will have that width reserved. The right-hand (or outside) side will have the remainder. A common option is to set this variable to zero and set latex.fancyhdr.truncation.style to “io”.