after doing a clearValue(), there are errors , and getValue() will not work anymore
is seems the bounlist has (after doing clearValue) an extra param, that is part of the selection, and make this bug happen
Edit1: sorry it's not a bug, I had changed the file ux/form/multiselect to be configurable as singleselelect also,
multiSelect: false,
singleSelect: false,
line 186
The bug after clearing values, only appear with those settings