XS_DRAWINGS_LINE_CAP_STYLE
Category in Advanced options dialog: Printing
Use this advanced option to adjust the shape of the line ends in PDF printouts by defining the line cap style. Enter one of the following values:
0 = Lines break in corners. This is the default value and the old way of printing the line ends.
1 = Round corners (recommended)
2 = Rectangular corners
Value 0:

Value 1:

Value 2:

This advanced option is model specific and the setting is saved in the options database.