I have written a Greasemonkey script which manipulates the contents of certain elements with the following selector:

```
$("span.relativetime").each(function() { $(this).html("TEST"); });

```

However, sometimes matching elements are added to the page through AJAX, and I don't know how to handle those new elements. I have tried this, but it doesn't work:

```
$("span.relativetime").live(function() { $(this).html("TEST"); });

```

The [documentation for jQuery live()](http://docs.jquery.com/Events/live) says that it wants an event (like "click"). But I don't have any event, I just want to know when something matching my selector has been created, and then I want to modify it.

**Background**: I am encountering this problem with a Greasemonkey script to display StackOverflow's relative timestamps as absolute local timestamps, which [you can find on meta-SO](https://meta.stackexchange.com/questions/12635/greasemonkey-script-to-display-absolute-timestamps-in-local-time). The problem is when you click "show all comments", the new comments are added by AJAX, and I don't know how to find and replace the timestamps in those scripts.