That work!
By the way, I added more code!
<script type="text/javascript" language="javascript">
function Update_sel_protocol (src)
{
var found=false;
for(var i=0;i<sel_protocol.options.length;i++)
{
var val=sel_protocol.options(i).value;
if(src.substr(0,val.length).toLowerCase()==val)
{
if(sel_protocol.selectedIndex!=i)
sel_protocol.selectedIndex=i;
found=true;
break;
}
}
//set others
if(!found)
{
sel_protocol.selectedIndex=0;
inp_src.value="http://";
inp_target.selectedIndex=1;
}
}
</script>
and, I disabled "browse" button also using below code.
<button id="btnbrowse" class="CuteEditorButtonDisabled" disabled>[[Browse]]</button>