Visible Errors

Visible Errors is a browser extension for Chrome, which shows you every JavaScript error on your pages visually, using a notification system similar to Growl. This can be used for developing web apps, when you may not always have the console open. The way JavaScript was designed, a single error doesn't necessarily stop execution of your web app. DOM events still execute, timers still fire, etc. Sometimes an error may be thrown but you may not even notice it. Visible Errors puts a stop to that. As a programmer, I want to see every error thrown by my apps, whether I have the console open or not.

Visible Errors shows notifications right in the page on which the errors occurred, in the top-right corner of the window. They have a "fixed" position, so they aren't affected by scrolling. If you have IFRAMEs in your app, they'll appear inside the frame, when appropriate.