(Action) Issue 448: Proposed modification to Note after checkpoint 5.9 (DOM2 CSS)

Hello,

At the 18 Jan 2001 teleconf [1], I received an action item pertaining
to issue 448 [2]. Checkpoint 5.9 in the 16 Jan 2001 draft [3] reads:

    For user agents that implement Cascading  
    Style Sheets (CSS), provide programmatic access 
    to those style sheets by conforming to the CSS module 
    of the W3C Document Object Model (DOM) Level 2 Style
    Specification [DOM2STYLE] and exporting the interfaces 
    it defines.

The reviewer's question was: Does this checkpoint require
read/write access?

I conferred with Philippe Le Hegaret (the DOM WG Team contact),
and here are the facts about the CSS module of the DOM Level 2
Style Specification [4]:

a) The CSS module does not provide access (read or write)
   to user style sheets. Apparently, one reason for this decision
   by the DOM WG involved privacy concerns.

b) The CSS module allows authors to modify author style sheets. 

c) The CSS module allows read access (but not write
   access) to the computed value of a CSS property.

d) The CSS module includes a mechanism called the
   "override style sheet". This style sheet is part of the 
   cascade (though not defined by the CSS Recommendation). It
   is used for in-memory modifications to author styles; these
   style changes are not saved with the DOM tree when it is written.

The two write mechanisms that are available through these 
APIs are intended for authors only. Therefore, I propose:

1) That we make no changes to the checkpoint requirement to
   implement the DOM 2 Style Recommendation.

2) That we add this text to the Note following the checkpoint:

     User agents should not allow users to modify author
     style sheets or the override style sheet through the
     mechanisms of the DOM Level 2 CSS module. Similarly,
     user agents should not allow authors to modify user
     style sheets. See checkpoint 4.14 for more information 
     about user control of user style sheets.


 - Ian

[1] http://lists.w3.org/Archives/Public/w3c-wai-ua/2001JanMar/0098.html
[2] http://server.rehab.uiuc.edu/ua-issues/issues-linear-lc2.html#448
[3] http://www.w3.org/WAI/UA/WD-UAAG10-20010116/
[4] http://www.w3.org/TR/2000/REC-DOM-Level-2-Style-20001113
-- 
Ian Jacobs (jacobs@w3.org)   http://www.w3.org/People/Jacobs
Tel:                         +1 831 457-2842
Cell:                        +1 917 450-8783

Received on Thursday, 18 January 2001 19:10:16 UTC