XS_DRAW_ROOT_OPENING_EVEN_WHEN_ZERO
Category in Advanced options dialog: Welds
Set this
advanced option to TRUE to show zero root openings in welds. The default is TRUE. If you set this
advanced option to FALSE, the zero root openings are not shown.

Root opening is the space between welded parts. Root opening value is only shown for weld types 3 and 4 (bevel-groove single-V butt and bevel-groove single-bevel butt welds).
This advanced option is role specific. When the type SYSTEM(ROLE) is in use, the default value is used. When the type MODEL(ROLE) or DRAWING(ROLE) is in use, you can change the value, which is then the same for all users in the current model.