Toggle Element State with Google Chrome and Mozilla Firefox
It's much easier to debug CSS than JavaScript since there are many fewer interactions in CSS, and they are much easier emulate. Still, element state debugging isn't simple...until now. Google Chrome's WebInspector and Mozilla Firefox's Firebug have a really sweet feature I just discovered which allows the developer to apply element states for the sake of debugging.
Chrome's WebInspector

The image above displays Chrome's "Toggle Element State" button, allowing developers to toggle CSS states via checkboxes.
Firefox's Firebug

The image displays Firebug's likewise menu, triggered by the down arrow on the CSS tab for an element.
This allows active CSS state bugging vs. simple CSS explorations to be much, much easier. Happy CSS debugging!
![Create Namespaced Classes with MooTools]()
MooTools has always gotten a bit of grief for not inherently using and standardizing namespaced-based JavaScript classes like the Dojo Toolkit does. Many developers create their classes as globals which is generally frowned up. I mostly disagree with that stance, but each to their own. In any event...
![CSS @supports]()
Feature detection via JavaScript is a client side best practice and for all the right reasons, but unfortunately that same functionality hasn't been available within CSS. What we end up doing is repeating the same properties multiple times with each browser prefix. Yuck. Another thing we...
![Create a CSS Flipping Animation]()
CSS animations are a lot of fun; the beauty of them is that through many simple properties, you can create anything from an elegant fade in to a WTF-Pixar-would-be-proud effect. One CSS effect somewhere in between is the CSS flip effect, whereby there's...
![Create a Photo Stack Effect with Pure CSS Animations or MooTools]()
My favorite technological piece of Google Plus is its image upload and display handling. You can drag the images from your OS right into a browser's DIV element, the images upload right before your eyes, and the albums page displays a sexy photo deck animation...
Great tip, thanks =)
FireBug does this for years. Just click the little arrow next to the style tab. It’s only
:hoverand:active, though.Awesome, just added that as well.
The only thing Chrome cant do with states is when I need to debug an element that matches selector
parentElement:hover element, for exampleChrome applies states only to selected element in inspector and when you selected another element, selected state is applied to new element
Next challenge: Debug pseudo elements with web inspector :p
the Chrome web inspector already supports pseudo elements.
Under the Matched CSS rules is a Psuedo element
I believe the latest version of firebug does similar, but I’m not sure as I haven’t used it in ages
Unfortunately you can not select the pseudo element like any other DOM-Element. Technically this is perfectly valid since pseudo-elements are not part of the DOM but I often miss that feature. Pseudo-elements are harder to debug than necessary.
Good stuff, from what I know this has been around for a while already.
@JAN BECK – not that hard really, you just have to select the main element and scroll down in the inspector panel to see the psuedo elements
it’s also possible to do this with Firefox’ built in developer tools :-)