code: public String getAdditionalPreference(String name, boolean useDefault) {
  
          String value = m_additionalPreferences.get(name);
          if ((value == null) && useDefault) {
              I_CmsPreference pref = OpenCms.getWorkplaceManager().getDefaultUserSettings().getPreferences().get(name);
              if (pref != null) {
                  value = pref.getDefaultValue();
              }
          }
          return value;
      }
docs: Gets the value for a user defined preference.<p>
  
  @param name the name of the preference
  @param useDefault true if the default value should be returned in case the preference is not set
  
  @return the preference value