Firstly, everything in ziesemer’s answer is correct. This is all about JavaScript history There are a number of functions that are available in various browser’s devtools consoles. Collectively, the methods are known as the Command Line API(off-line) (new link) and they all originate from Firebug. Nowadays we just have parity across browsers because Firebug did … Read more
Did you look at webkit remote debugging protocol? It seems they know people want a debugger for their iPad but still no real world native iPad remote debugger is available out there. But don’t get disappointed, there is a tool called weinre that doing what webkit folks willing to do in the future right now! … Read more
use one of these commands: cd(frames[0]) cd(frames[“iframe_canvas”]) and cd(top) to return to the main window. Still, due to a bug this currently doesn’t work on cross-domain-iframes (http://code.google.com/p/fbug/issues/detail?id=3893). There are two test cases where you can test your evironment for both cases: https://getfirebug.com/tests/content/commandLine/cd.html (same domain, works for me: FF 3.6.13, FB 1.6.2) http://getfirebug.com/tests/issues/3893/issue3893.html (cross domain, fails) … Read more
Step into will cause the debugger to descend into any method calls on the current line. If there are multiple method calls, they’ll be visited in order of execution; if there are no method calls, this is same as step over. This is broadly equivalent to following every individual line of execution as would be … Read more
In Chrome Dev Tools: If you go to Settings>Overrides>Device metrics If you swap the dimensions for the screen resolution the orientation will change and the orientationchange-event will be triggered. The orientation is depending on the relationship between ‘width’ and ‘height’. If ‘height’ has a higher value than ‘width’, the browser will be in orientation: ‘portrait’ … Read more
(source: fidelitydesign.net) You can use the Firebug Console tab to write Javascript. I use this quite a lot of rapid prototyping of code before I integrate it into my projects. When you use the Console, javascript is executed in the context of the current page. Therefore, and scripts that are currently defined for that page, … Read more
Beautify your script Add the CDN host in /etc/hosts or your local DNS to resolve it to your own web server Host the beautified version and everything that you need on said web server Both Firefox and Chrome (versions as of this edit) support beautifying script with the {} button available in the inspector.
The problem with editing JavaScript like you can CSS and HTML is that there is no clean way to propagate the changes. JavaScript can modify the DOM, send Ajax requests, and dynamically modify existing objects and functions at runtime. So, once you have loaded a page with JavaScript, it might be completely different after the … Read more
Original answer: Check for the console object (created only with Firebug), like such: if (window.console && window.console.firebug) { //Firebug is enabled } Update (January 2012): The Firebug developers have decided to remove window.console.firebug. You can still detect the presence of Firebug by duck typing like if (window.console && (window.console.firebug || window.console.exception)) { //Firebug is enabled … Read more
What about Web Developer Toolbar? https://addons.mozilla.org/en-US/firefox/addon/60 when installed go to CSS -> Display CSS by media type -> Print