• log4javascript
• Blackbird

Some pros and cons:

log4javascript is very powerful. It contains lots of options, it has timers, several appenders (in page or using a popup window), the console supports tons of filters. If you know log4j, you’ll find almost everything replicated. If you need fewer options, there is even a lite version.

Despite the many options, log4javascript is still simple to set up and use (so it’s not like log4j in every respect). The default setup needs 3 lines of code (not counting the script element to load the framework).

There are two minor points: The console is pretty big and the in-page version can’t be moved.

Blackbird is a really small logging framework. No frills, just the basics. So no exception logging, for example. A profiling option is the most complex feature. In the world of the logging frameworks, it’s the iPhone: Nice look and only the useful features. The console is always in page, it sits in one of the four browser corners, it can be hidden and shown with F2.

My main complaint about Blackbird is that you can’t use the mouse to move the console. Also disabling the framework needs several lines of code. A single variable would have been more comfortable.

MIT License, impressive demos, readable source code.

It contains a sane project layout, many useful JavaScript libraries, a default CSS that will make your page look the same on (almost) any device and smart CSS selectors that allow you to work around problems with browsers and devices which don’t behave well (small screen, IE6 bugs, no JavaScript enabled, you name it).

aqu4rium is a demo for a GWT based game framework which mimics an older IE9 demo Fishietank. My numbers: 250 fish, ~56FPS, load 0.1.

ro.me is a 3D music video with interactive effects. After the video, you’ll be redirected to a page with lots of technical details, source and example code.

Apparently, Jonathan Sharp had the same problem and created a solution: Mock Your Ajax Requests with Mockjax for Rapid Development

Very nice. Thank you!

JavaScript has come a long way.

Image via Wikipedia

It’s 2010, Firefox is going 4.0 soon and it still has no way to tell why it’s sluggish.

Yes, it would be nice if the FF developers could make the browser so fast that it would never become sluggish in the first place. I just fear that this is simply not possible with the current design. Look at Chrome: Every tab runs in it’s own process. So what if one of them is slow? All the other still feel crisp.

On FF, if one tab takes over the machine, you’re doomed. Yes, I could disable JavaScript and every add-on individually. Why bother? Starting Chrome solves the issue in no time.

If you care, support Bug 505104: Please add a tool to gauge Addon performance.