Answers for "html select remove all options"

remove all options from select jquery

$('#mySelect')
    .empty()

Alll select options unselectable

<div 
 style="-moz-user-select: none; -webkit-user-select: none; -ms-user-select:none; user-select:none;-o-user-select:none;" 
 unselectable="on"
 onselectstart="return false;" 
 onmousedown="return false;">
    Blabla
</div>