Solving: Permission denied to get property HTMLDivElement.nodeType when calling method: [nsIDOMEventListener::handleEvent] nsresult: 0×8057001e (NS_ERROR_XPC_JS_THREW_STRING) location: data: no

This is a sporadic error that I have seen in Firefox browsers while using the Ext JS components. It is not harmful in any way but is annoying. It is filed as a Firefox defect and has been fixed for 3.0a5pre. In the earlier version here is how you can fix it for Firefox.

Adding autocomplete=”off” to all the text fields will fix it. It is an internal Firefox error and causes no problem as such. Personally I am choosing to ignore it.