This paragraph is within a <div>, and its width is set by stylesheet to be 23 em wide. To see the bug, hold the control key and press the '-' key (to make the font face smaller) or the '=' key (to make the font face bigger). Note that the width of the div, which is set by the 'em space' of the font face, does not follow changes in the font face.

The style for this div is: div {width: 23em; margin-left:2em; margin-right: 2em;}