Firefox always updating java console
This content refers to an older version of F12 developer tools. The F12 tools console commands let you receive error messages from Windows Internet Explorer 9, as well as send your own messages back from your code without having to break the flow of your execution.
You can use the F12 tools console view to immediately run script statements outside your program code.
Type script into the multiline window, and then click the Run script button to execute.
You can change to iframes by using an ID name, or by using the frames collection.
In this case, "document.frames" works just as well.
You use the console object to send a message to the console from your code.
Using the console instead of "window.alert()" when testing code is less obtrusive and doesn't stop you with a modal dialog box.