Bug: clearable does not work for multiple selects

[joelmukuthu]

From this issue #344, it appears that clearable was designed to work also for multiple selects, but that doesn't seem to be working. Repro: https://svelte.dev/playground/eabbf59abaa24155a7126f05f2ddd5f2?version=4.2.19.

I'd expect that when clearable is set to false, the preselected item cannot be removed, be it by clicking x on the selected item or by pressing the backspace key.

Am I mistaken or is this a bug? Or is there a workaround to prevent clearing the preset value for multiple selects?