Yes, it's not MozRepl-specific, but to listen for web page loads when you are in chrome (like you are when you're using MozRepl) one way might be:
getBrowser().addEventListener('load', function(event) { myOnLoadHandler(event); }, true);
Keep in mind that myOnLoadHandler will be invoked on every page load, not just the next one.
You can probably find useful snippets on http://developer.mozilla.org and perhaps something in the archive of http://groups.google.com/group/mozlab.
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Yes, it's not MozRepl-specific, but to listen for web page loads when you are in chrome (like you are when you're using MozRepl) one way might be:
Keep in mind that myOnLoadHandler will be invoked on every page load, not just the next one.
You can probably find useful snippets on http://developer.mozilla.org and perhaps something in the archive of http://groups.google.com/group/mozlab.