Konfabulator has a mode of operation that's known as Debug Mode. This mode lets you type JavaScript to be evaluated while your Widget is running, and thus it can be an invaluable tool for debugging your Widget. Also, when people find problems using your Widget, it can be helpful to have them go into Debug Mode and report some information to you. Here is a screenshot of the debug window in action: You can enable Debug Mode in a variety of ways. The simplest way involves a few clicks and keypresses. You can also modify your code to always launch in a particular mode.