271274 - Right-floating div's width does not match right margin of another div

Status: RESOLVED WORKSFORME

(Core :: Layout: Floats, defect)

Description

[Marten Klencke]

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

When there is a block div with a right margin of a specific number of pixels and
a float to cover this right margin exactly, sometimes the float doesn't cover
enough.

Reproducible: Always
Steps to Reproduce:
1. Maximize the browser window on the example URL
2. Slowly decrease the horizontal size.
Actual Results:  
At some point a vertical line will show up in the blue top bar. This should not
occur since margin-right of the main bar and the width of the top right float
are equal. This remains also when the page is reloaded with a visible vertical line.

Expected Results:  
The vertical white line should not be there. The float should always exactly
cover the margin.

To workaround, simple make the margin slightly less than the width of the float.

Comment 1

[Boris Zbarsky [:bzbarsky]]

This needs a minimal testcase...  Looks like a rounding issue somehow, though.

Comment 2

[Uri Bernstein]

Attachment: testcase

This is as small as I could get. I fixed the body width (to 594px) so no window
resizing is required to see the white line.

Comment 3

[Boris Zbarsky [:bzbarsky]]

Uri, thanks!  Definitely a rounding issue.

Comment 4

[Uri Bernstein]

This WFM since 2005-03-29 trunk builds. Not sure what fixed it.