When the font size of static text is set as 11.5, 10.5, 9.5 etc. (not round, like 11.0 or 10.0) the part of the text behind the last line break character ("\n") disappears in exported PDF. (Exporting to HTML works fine.) It helps to add a line break after the last paragraph.
Similar issue is described for version 3.1.4 here: