Question: I am trying to add a highlight color to a class like this

```
    $(".common_box").hover(function(){
        $(".common_box").addClass("hover_me");
    });

```

this works but why doesnt this

```
    $(".common_box").hover(function(){
        $(".common_box").toggleClass("hover_me");
    });

```

when i hover over this nothing happens

is there no unhover to put to remove the class hover\_me when they move away from the hover

Answer: 
There's currently a bug in some situations where the mouse enter/leave events are firing twice, so it *is* working, but it's double toggling each in/out, so no net effect...for now, to be safe:

```
$(".common_box").hover(function(){
    $(this).addClass("hover_me");
}, function(){
    $(this).removeClass("hover_me");
});

```

This is a bug (I *believe*) because of the [`.live()`](http://api.jquery.com/live/) changes to support [`.hover()`](http://api.jquery.com/hover/), which is causing some unwanted side-effects, you can be explicit like above to be 100% safe, so if each handler runs multiple times, at least for your purposes, it's alright.
Try this

```
  $(".common_box").mouseover(function() {
    $(this).addClass("hover_me");
  }).mouseout(function(){
    $(this).removeClass("hover_me");
  });

```