If one goes to "My notification settings" and add some items to "My item notifications", these subscriptions can not be removed because "Remove selected" button is inactive.

The bug caused by error in new admin2 interface template:

/design/admin2/templates/notification/handler/ezsubtree/settings

        {if $subscribed_nodes}
        <input class="button" type="submit" name="RemoveRule_ ...

should be replaced with

        {if $subscribed_nodes_count}