When selected a group, if you want to deselect all group, it does nothing. That is because the new value returned in this case, its not filtering correctly.
I've solved the problem with the following filter:
const newValue = this.internalValue.filter( (option) => !group[this.groupValues] .map((item)=>item.id) .includes(option.id) );
https://github.com/shentao/vue-multiselect/blob/30667d0e0225dcbb0510dc342e109137a1dcfcab/src/multiselectMixin.js#L567
When selected a group, if you want to deselect all group, it does nothing. That is because the new value returned in this case, its not filtering correctly.
I've solved the problem with the following filter:
const newValue = this.internalValue.filter( (option) => !group[this.groupValues] .map((item)=>item.id) .includes(option.id) );