107417 - display: block should set a default max-width equal to the width of the containing block

Status: RESOLVED INVALID

(Core :: Layout, defect)

Description

[PTRourke]

When using display: block in CSS on an element (in the test case, an XML
element), if max-width is not set and width is not set, the element should be
treated as though it had a max-width of 100%, which should be calculated from
the width of the containing block (making allowance for margins, padding, etc.).  

Right now, Mozilla sets no default max-width on elements, so that they run well
past the viewport if there is no max-width set.  In addition, if max-width is
set at 100%, the effect seems to be to set the width at 1em or 100 pixels.

I'll attach two files as demos.

Comment 1

[PTRourke]

Attachment: Test case: XML file with elements to be treated as block-level elements

Comment 2

[PTRourke]

Attachment: Test Case: CSS file with display: block attributes.

Comment 3

[PTRourke]

> the effect seems to be to set the width at 1em or 100 pixels.

Sorry, this should make the report a little clearer: 

for "1em or 100 pixels" switch "some abitrary width (perhaps 1em or 100 pixels?)"

2001102903 Win98 SE

Comment 4

[Jason Johnston]

Note that since the root element (<notices/>) has no "display" property set, it
defaults to "inline" per the CSS spec.  We therefore have several block elements
within an inline element, which is technically not allowed.

Adding display:block to the root element gives us the expected behavior.

Comment 5

[PTRourke]

Got it.  Spec does say initial value is inline; Amaya 5.2 provided the behavior 
I expected, which is permitted, but apparently not the preferred (CSS2 spec):  

[quote]
Note that although the initial value of 'display' is 'inline', rules in the 
user agent's default style sheet may override this value. See the sample style 
sheet for HTML 4.0 in the appendix. 
[/quote]

while IE failed to render properly (giving the correct size on the child 
elements, but flaws in the color rendering) until display on root element was 
set to block.  Marking own bug invalid.  Thanks, Mr. Johnston.