How can you get a screenshot from someone's web browser?

Question

I didn't think this was possible, but http://www.snapabug.com provides a service that uses screen capture technology to generate reports that helps you help your users. How are they able to do this??

Apparently, their service does not require any extra browser plugins or extensions. My guess is that it uses Flash, since this doesn't seem possible in JavaScript, and loading a Java applet is ridiculously slow.

Answer 1

SnapABug uses a Java Applet to get the screenshot of the Browser. A Java Runtime Environment is listed as one of the Technical Requirements.

This blog post details how the Java Applet captures the image from the browser.