[web] How to debug html/javascript properly?

Hi !

I wrote a browser game about 10 years ago and thought I lost it, but was able to recover it from an old backup cd lately :)

It was quite easy to make it run on a current php version (I wrote it back on php3 with magic quotes on etc.). Just minor modifications though.

Back in 2000, Internet Explorer was dominating, followed by a few netscape users and hardly anyone used Opera. So, back then, I went and made it work with IE. Surprisingly, after all what has happend in the browsers history, it still works (except for screen.availWidth and availHeight got case sensitive somewhen :/). But it absolutely doesn't work on any other current browser. :(

I don't think there is too much wrong for them, some things I was able to figure out, but most of the time, it's like: when I click something, in IE it happens, but in FF just nothing happens. So my question is: Is there a tool for &#106avascript debugging that somehow tells me what's wrong? It's strange that nothing really happens instead of displaying an errormsg somewhere. I tried the firefox addons FireBug and &#106avascript Debugger so far, but the first doesn't seem to be targetting &#106avascript debugging (or I don't know how to use it correctly) while the 2nd reveals that a lot of &#106avascript functions seem to be implemented in &#106avascript itself in ff and I get lost in some internal ff &#106avascript :/<br><br>I installed the game &#111;nline if you want to have a look: <a href="http://www.confrontation-unlimited.net/cuweb">Confrontation Unlimited Web</a> It's a persistent &#111;nline strategy game with a map and units you can move around &#111;n it and build buildings.<br><br>I have to apologize because the website is in german but the game itself is in english, no idea why I did it back then :D, but the registration is as well in english: <a href="http://www.confrontation-unlimited.net/cuweb/game/anmeldung.php">registration</a> and you can login from the start page.<br><br>The registration link from above is already the first page that doesn't work in ff without any comment. If you try that page in IE, you can change the background color of your empires emblem by clicking &#111;n those color bars. In ff, that doesn't work - all the other &#106avascript I was able to make it work, like changing the layers of the emblem.<br><br>There are more of those issues inside the actual game so a general approach for debugging &#106avascript is of interest to me.<br><br>Thx :)<br> Marc