How do I populate a webform component with a %_GET variable token? I have webform 4 enabled. I just created a textfield component and set its default value to %get[my-key]. But the token is not working at all. I also tried with %_get[my-key] and [%get[my-key]] but is not working neither.

As far as I understand Webform 4 in not working anymore with POST variables in favor of GET variables. 

How can I get the GET variables?
I use tokens to get keys from the URL. The token for the %get variable would be [current-page:query:?], where the ? = the query name in the url. For example, if your url is mysite.com/page?foo=bar, you would use [current-page:query:foo] to return "bar".