280306 - "id" attribute in DIV tag is treated as case-insensitive string, contrary to HTML 4.01

Status: RESOLVED WONTFIX

(Core :: CSS Parsing and Computation, defect)

Description

[Richard Chonak]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20041107 Firefox/1.0
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20041107 Firefox/1.0

In the page at http://www.gabrielmass.com/tmp/id-attribute.html, the DIV with
ID="main" is displayed with padding on all four sides.   

That is, it gets CSS attributes from styles "#main" and "#Main".  However, 
according to the HTML 4.01 spec at 
http://www.w3.org/TR/REC-html40/struct/global.html#h-7.5.2, the ID attribute is
case-sensitive, so only one of those styles should be used.



Reproducible: Always

Steps to Reproduce:
1. view http://www.gabrielmass.com/tmp/id-attribute.html

Actual Results:  
The DIV block is displayed with top- and bottom-padding of 50px.


Expected Results:  
The top and bottom padding should have defaulted to 0.

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

This works correctly in standards mode but is an intentional bug in quirks mode,
since many Web pages depend on it.  See
http://www.mozilla.org/docs/web-developer/quirks/ .