I think I know why, actually not the sidebar problem but the widget in the sidebar have some problem, i am not sure if that is javascript conflit, the widget is events manager, this is the events calendar widget:
<?php
/**
* @author marcus
* Standard events calendar widget
*/
class EM_Widget_Calendar extends WP_Widget {
var $defaults = array();
/** constructor */
function EM_Widget_Calendar() {
$this->defaults = array(
'title' => __('Calendar','dbem'),
'long_events' => 0,
'category' => 0
);
$widget_ops = array('description' => __( "Display your events in a calendar widget.", 'dbem') );
parent::WP_Widget(false, $name = __('Events Calendar','dbem'), $widget_ops);
}
/** @see WP_Widget::widget */
function widget($args, $instance) {
$instance = array_merge($this->defaults, $instance);
echo $args['before_widget'];
if( !empty($instance['title']) ){
echo $args['before_title'];
echo $instance['title'];
echo $args['after_title'];
}
//Shall we show a specific month?
if ( !empty($_REQUEST['calendar_day']) ) {
$date = explode('-', $_REQUEST['calendar_day']);
$instance['month'] = $date[1];
$instance['year'] = $date[0];
}else{
$instance['month'] = date("m");
}
//Our Widget Content
echo EM_Calendar::output(apply_filters('em_widget_calendar_get_args',$instance));
echo $args['after_widget'];
}
/** @see WP_Widget::update */
function update($new_instance, $old_instance) {
//filter the new instance and replace blanks with defaults
$new_instance['title'] = (!isset($new_instance['title'])) ? $this->defaults['title']:$new_instance['title'];
$new_instance['long_events'] = ($new_instance['long_events'] == '') ? $this->defaults['long_events']:$new_instance['long_events'];
$new_instance['category'] = ($new_instance['category'] == '') ? $this->defaults['category']:$new_instance['category'];
return $new_instance;
}
/** @see WP_Widget::form */
function form($instance) {
$instance = array_merge($this->defaults, $instance);
?>
<p>
<label for="<?php echo $this->get_field_id('title'); ?>"><?php _e('Title', 'dbem'); ?>: </label>
<input type="text" id="<?php echo $this->get_field_id('title'); ?>" name="<?php echo $this->get_field_name('title'); ?>" value="<?php echo esc_attr($instance['title']); ?>" />
</p>
<p>
<label for="<?php echo $this->get_field_id('long_events'); ?>"><?php _e('Show Long Events?', 'dbem'); ?>: </label>
<input type="checkbox" id="<?php echo $this->get_field_id('long_events'); ?>" name="<?php echo $this->get_field_name('long_events'); ?>" value="1" <?php echo ($instance['long_events'] == '1') ? 'checked="checked"':''; ?>/>
</p>
<p>
<label for="<?php echo $this->get_field_id('category'); ?>"><?php _e('Category IDs','dbem'); ?>: </label>
<input type="text" id="<?php echo $this->get_field_id('category'); ?>" name="<?php echo $this->get_field_name('category'); ?>" size="3" value="<?php echo esc_attr($instance['category']); ?>" />
<em><?php _e('1,2,3 or 2 (0 = all)','dbem'); ?> </em>
</p>
<?php
}
}
add_action('widgets_init', create_function('', 'return register_widget("EM_Widget_Calendar");'));
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