Question: I am trying migrate to Selenium 2 (WebDriver) from Selenium 1 (rc). 

I have replaced the below code with the Firefox driver upon which my browser opens and runs:

```
Selenium selenium = new DefaultSelenium(
    "localhost", 4444, "*firefox", "http://www.yoursite.com");
selenium.start();

```

My problem is that Selenium cannot find any elements using XPath or CSS, just id seem to work so far. I have tried using different XPath and css locators, as well as DOM, but they don't work. The Selenium migration guide said finding elements by XPath or CSS Selectors does not always work but they don't seem to work for me at all.

Below is an example of an element I am trying to identify along with the CSS identifier I am trying to use, which works in selenium 1 and in the Selenium IDE :

```
<div id="GUID_3" class="DA_COMPONENT DA_SPEEDBUTTON" style="line-height: 16px; cursor: default;" title="Actions">

css=[title='Actions']

```

Answer: 
[When can I use...](http://caniuse.com) contains browser support tables with convenient indicators of which versions of which browsers require the vendor-prefixed versions of various CSS3 features, as well as features in other standards like HTML5, its new JavaScript APIs, SVG, etc. That should be the first place you stop at.

The site is updated regularly (for now, at least) as new versions of browsers are released and the drafts of the relevant CSS3 modules are updated.
<http://html5please.us/> Offers a similar service but they also provide advice on fallbacks for CSS3 properties where appropriate. I find both sites useful.