If you haven’t seen Firebug then you’re definately missing out. Firebug has been out for quite a while, it’s nothing new; but I think it never got the attention (especially in .NET developer circles) it deserved.
Once, at a convention I brought up that Firebug had javascript debugging capability for a long time while Visual Studio waited until 2008 to really offer it.
Let me make sure I’m not confusing anyone, Firebug is just an addon to FireFox and is not a development environment. It is however a great tool for developers working on multiple browsers to debug javascript and peak under the covers of their web resources and clientside processing.
Here are some nice screenshots I just made of how I use Firefox:
Screenshot of Resources Loading Clientside
You can list your resources that are loading (images, external files, etc.). By doing so, you can see load times as well as broken links or clientside errors (marked in red) while loading.
Screenshot of Javascript Debugging in Firefox
Javascript debugging has always been a bit of a pain. With Firebug you can use a familiar system of breakpoints and even an Immediate-style window to check variable values, etc.
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