Kodu şu şekilde duzenledim fakat başarılı sonuç alamadım.


<div class="form-group select-placeholder">
							<label for="assigned" class="control-label">
								<?php echo _l('ticket_settings_assign_to'); ?>
							</label>
							<select multiple name="assigned[]" id="assigned" class="form-control selectpicker" data-live-search="true" data-none-selected-text="<?php echo _l('dropdown_non_selected_tex'); ?>" data-width="100%"> 
								<option value=""><?php echo _l('ticket_settings_none_assigned'); ?></option>
								<?php foreach($staff as $member){ ?>
									<option value="<?php echo $member['staffid']; ?>" <?php if($member['staffid'] == get_staff_user_id()){echo '';} ?>>
										<?php echo $member['firstname'] . ' ' . $member['lastname'] ; ?>
									</option>
								<?php } ?>
							</select>
						</div>