Browsers compatibility issues

• Hi people .
  
  I'm now having the "enormous pleasure" to make a web site we're developing compatible for the "non-IE" browsers , such as Netscape and Firefox .
  
  Since most of our web applications are written for inside use of organizations (on the Intranet) ,
  we always rely on the fact that the clients are using IE and even of a specific version, and that , is actually a part of the application requirements in the
  design document.
  
  Based on that , we have many written client side code that we re-use in every application that will work in IE , but was never tested on other browsers.
  
  But now the site we develop is going to be on the Internet , and the client demands that it should support not only IE , but other "known" browsers too.
  
  So now I'm going over the html , css , code and try to make it work "for all".
  
  Changes include :
  
  
  

1. DOM properties/methods use
   
   There are many properties and methods that are either do not exist in other browsers , or called differently.
   
   
2. CSS stuff
   
   Some styles are not supported , or syntax/names are different.
   
   
3. XMLDOM properties/methods use
   
   Mozilla does not use the MS XMLDOM activex , instead they use their own implementation of XMLDOM.
   
   Hence some methods/properties do not exist/called differently.
   
   
4. HTML
   
   Mozilla handles HTML not "exactly" like IE ..
   
   So if you write a simple plain text in your page , without use of any html tags - it's probably will look the same in all the browsers .
   But obviously you do more than that .
   So you have to play with it to reach a "common html level" so that pages will look good and similar in all the browsers.

In mostly all of the mentioned above issues it seems that those Mozilla browsers are the trouble-makers . But if you think deeper - they are not.
They claim to use the W3C standarts and claim to be strict about this .

I use the word "claim" since I haven't tested it -
and maybe they're actually not .

But anyhow - Microsoft has implemented many stuff ( in CSS , DOM )
over the years , that are pretty usefull and we already take that for granted , and use it all over.

These MS-standarts somehow became "world-standarts" , since when most people develop sites , they think : "it's 99% IE out there" .

So they develop "by MSDN" .

The problem is that those standarts are still MS only ..

And though they are great and everyone loves using them.. they aren't supported in other browsers .


Now .. this issue of Ms standarts - I don't know whether this was done intentionally by MS over the years , with the purpose to dominate the browsers world,
or whether their purpose was pure and only for "making the world better place to live in".

So it's actually their fault that I'm awake now at 05:30 AM writing those thoughts.

I've found plenty of information regarding compatibility issues over the web .
Some in forums and some in articles .

After I'm done with this mission - I will post some summary of addoptations and links to articles I've found .

Wish me luck...