JavaScript Debugger and Trace Tool

Hi, people.
Here is the tool that i wrote it for my self,
i sick of using alert() and i wrote a trace tool.
it can show you the errors also you can use it to prompt any thing on it, just like using alert().
also you don't have to add any code onto your site. just call the trace.js at very top of your page and it will run it by itself.
to promp on screen just use it like alert() but call it as trace("helloworld");
it's quite simple. it work on almost all browsers.
best part is, this tool is in a floating windows so this means you can place it anywhere in your page.
You can see the working version here
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There is a watch property I currently added. watch is not perfect but at least you can fallow hidden fields or that kind of thing by just giving their id's.
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you can find the code here