7660 - <map> causes extra whitespace; shouldn't be displayed

Status: VERIFIED FIXED

(Core :: CSS Parsing and Computation, defect, P3)

Description

[Sam Allen]

The <map> tag at the top of http://www.mozilla.org/ is causing there to be
extra whitespace at the top of the page. The fix for this is very easy.

Add, to ua.css,

map {display: none; }

Voila! Whitespace is gone, on mozilla.org and the other pages that exhibit this
flaw. This does not cause any functionality of the tag to be lost.

Someone check this in, that whitespace has been bothering me for a long time.

Comment 1

[rickg]

Kipp -- this looks to be a box/line collapsing bug. Note the first blank line
that preceeds the map (at the very top of the page).

Comment 2

[Hixie (not reading bugmail)]

The problem is actually that MAP is currently not mentioned in ua.css, so it
defaults to being an inline element. It thus creates an anonymous block box
around itself, takes note of itself because it is empty, and leaves a blank
line. This is correct as per CSS.

To follow HTML4, it should be declared like this:

   MAP { display: block; }

It would be wrong to say "map { display: none; }", because otherwise block-level
content in MAP elements would dissapear. See HTML4, section 13.6.1.

I am reassigning this to Style System.

Peter: The fix for this is really simple, just add the line mentioned above
to ua.css, near the AREA rule.

Comment 3

[Hixie (not reading bugmail)]

Reassigning...

Comment 4

[Chris Petersen]

OK.Checked with the 6/23 build. Marking as verified fixed.

Comment 5

[Hixie (not reading bugmail)]

*** Bug 8846 has been marked as a duplicate of this bug. ***

Comment 6

[Sam Allen]

*** Bug 9273 has been marked as a duplicate of this bug. ***