From Bugzilla Helper: User-Agent: Mozilla/4.77 [en] (X11; U; Linux 2.4.3 i586) BuildID: 2001042106 Mozilla incorrectly renders text elements inside block elements, causing them to extend partially outside of their containing elements. Reproducible: Always Steps to Reproduce: 1. Open http://www.w3.org 2. Examine the banner links (directly beneath the logo) or the items in either sidebar. Actual Results: The top of the banner links extend above the top of their containing DIV and the bottom of the items in the sidebars are clipped by the item immediately below. Expected Results: Everything renders correctly. :)

Hixie, what do you think of the testcase? The blue extends a pixel or two below the black.... as for the W3C site underlining problem, see bug 59825

Works for me on Windows... It's probably correct behaviour -- you're on Linux right? it just means we are using a slightly different size for the font than what the web page expected. Very nice screenshot and testcase, btw.

I don't think this is correct behavior. Inline elements should never extend out of their containing block elements, should they? Isn't the parent block supposed to grow to fully contain its children? Following is a slightly revised test case (text-size is no longer set) and a screen shot of how Mozilla renders it. Actually, I think this might be a duplicate of bug 59825, which I believe is definitely a bug in Mozilla and not a problem with the CSS spec. Ordinary text wrapping should not cause the lower portions of the previous line to be obscured, which is what happens in the test case for this bug (see the image of how Mozilla renders it).

Ok I think what you're actually seeing is related to a very obscure inline box model bug which was filed a while ago, namely bug 27164. On my Linux box, the inline background actually underruns the div's background. This is because the height of the background is the height of the bounding box, but the height of the line box is (or should be) the height of the em box. For this reason, the inline background CAN quite legitimately go outside the DIV's box. I'm pretty sure that the CSS spec doesn't say this is wrong. It all just depends on the font's metrics.

I'd have to check on what the font size and line height come out to in that test case to see whether this is an inline layout bug or a rounding bug of some sort. Assigning it to myself, unless somebody else wants to investigate it.

I think this is the same problem that causes scrollbars to appear on textareas on Linux after one character of typing, so I'll try to look at this in 0.9.2.

*** Bug 94364 has been marked as a duplicate of this bug. ***

Fix for bug 91794 checked in 2001-08-23 06:44 PDT. (There's still some funny stuff caused by the acronym[title], abbr[title] rule in our html.css, though...)