Giving the script tag an ID
I came across a scenario where giving a script element an id attribute would solve a problem easily. However, after reading about the script element at w3schools and quirksmode, it seems doing so could have some unforeseen consequences.
Has anyone come across any of these issues with browsers such as Chrome, Safari, FF3 up and IE 7 up?
It's fine in all current browsers.
The only browser that got <script id> wrong was Netscape 4, which we stopped caring about a long, long time ago.
That quirksmode page seems to be badly out of date, what with its use of language attributes, script <!-- hiding, and application/x-javascript. Its advice about avoiding <script> in the <body> (and putting it in <head> instead) is at odds with today's encouraged practices.
If we're talking <script> attribute compatibility problems: defer doesn't work everywhere so don't rely on it; charset doesn't work everywhere, and neither does the charset parameter on the served script's Content-Type, so your script charset had better match the page; type should always be text/javascript and not one of the non-working alternatives the pedants who wrote RFC 4329 would like you to use.
Keep in mind that setting the id on any element introduces a new global variable with the same name as the id attribute:
If you're still having to support Netscape 4, you've got a lot of trouble – and the pity and condolences of the rest of the developer world.
Short answer, I wouldn't worry about it.