message: Polygon offset clamp is core now
diff: <item row="1" column="4">
  <widget class="QLabel" name="offsetClampLabel">
  <property name="text">
  - <string>Offset Clamp (EXT):</string>
  + <string>Offset Clamp:</string>
  </property>
  <property name="alignment">
  <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
  