Note: There are a few cases of duplicates in user autocompletion which are being worked on.

[BC] Table cell border widths render incorrectly at various zoom levels




Layout: Tables
10 years ago
3 months ago


(Reporter: Chris Roat, Unassigned)


(Depends on: 2 bugs)

Dependency tree / graph

Firefox Tracking Flags

(Not tracked)



(2 attachments)



10 years ago
User-Agent:       Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9b2) Gecko/2007121014 Firefox/3.0b2
Build Identifier: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9b2) Gecko/2007121014 Firefox/3.0b2

When rendering tables, the width of the cell borders looks OK at the default zoom, but there seems to be an aliasing issue at other zoom levels.  Zooming in/out can cause borders that should be the same width appear different widths... including having thin borders disappear completely.

Reproducible: Always

Steps to Reproduce:
1. Save the xhtml below as a file.
2. Fire up FF beta2 (found on both OSX/Leopard and Ubuntu) and open the file.
3. Zoom in or out.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
<html xmlns="" xml:lang="en" lang="en">
<title>Firefox 3 Beta 2 Render Problem When Zooming</title>
<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
<style type="text/css">
body {
  background: #FFFFFF;
table {
  background: #00CCFF;
  border-collapse: collapse;
table td {
  border-color: #666600;
  border-style: solid;
  border-width: 0 0 0.5 0;
<tr><td>The quick brown fox</td></tr>
<tr><td>The quick brown fox</td></tr>
<tr><td>The quick brown fox</td></tr>

Actual Results:  
The yellow borders appear different widths at various zoom levels - some borders disappearing from view when zooming out.

Expected Results:  
Borders should appear the same width at each zoom level.

Comment 1

9 years ago
In Firefox 3 (3.0.4 on a Mac and 3.0.2 on Linux), for a table with 1px border similar to your example, I observed that when zooming out various segments of the borders both between cells and table border itself would disappear. The same table rendered correctly in Firefox 2. As I researched this problem I ran across a posting on another site that mentioned there is an option to "Zoom Text Only". 

When this feature is enabled, the table is rendered correctly. Try it for your example. I believe this is what you are looking for.

I would recommend that Firefox enable this option by default and let the user choose to zoom everything by disabling the option. This would provide consistent behavior between FF2 and FF3.
Created attachment 396547 [details]
Might be related to bug 477157.
Component: General → Layout
Depends on: 477157
Ever confirmed: true
OS: Mac OS X → All
Product: Firefox → Core
QA Contact: general → layout
Hardware: PowerPC → All
Version: unspecified → Trunk


8 years ago
Duplicate of this bug: 514096

Comment 5

8 years ago
Created attachment 398979 [details]
Screenshot showing 3 zoom levels
I think this would be layout: tables...
Component: Layout → Layout: Tables
QA Contact: layout → layout.tables


8 years ago
Summary: Table cell border widths render incorrectly at various zoom levels → [BC] Table cell border widths render incorrectly at various zoom levels


8 years ago

Comment 7

8 years ago
Bump. I have a number of users annoyed about this as well. Firefox 3.6 on Windows XP SP3.

The bug has also been confirmed on Ubuntu 9.10 and 10.4 -


7 years ago
Duplicate of this bug: 572093


6 years ago
Duplicate of this bug: 689165

Comment 10

6 years ago
Still broken with FF 7.

Comment 11

6 years ago
Bug still in FF 8 : Mozilla/5.0 (Windows NT 5.1; rv:8.0) Gecko/20100101 Firefox/8.0

For example use, leave all defaults except set border-collapse to "collapse", then press ctrl-minus, note that the bottom table border disappears. Press ctrl-minus again, now the top and right borders are missing.


5 years ago
Duplicate of this bug: 777708

Comment 13

3 years ago
Are there any known work-arounds? Zooming is more common than ever, especially now that high(ish)-DPI monitors are finally entering the PC market. Even IE11 does this correctly.

Comment 14

3 years ago
2014 and this is still an issue? Wow.
I'm using the zoom-feature to fix Wikipedia's awful new font-style, and now all tables on WP have missing lines. Of course, Cr and IE don't have this issue.

Comment 15

3 years ago
Trying with the testcase of comment 2, the regression-range for disappearing lines when zooming out (smaller) is



Bug 389628 - "Implement UI for full page zoom" [p=dao r=mconnor r+sr=sicking (for content/events/) a=blocking-firefox3+ for M9] 


And the range for disappearing lines when zooming in (bigger) is

Last good revision: a131999fa900 (2008-10-31)
First bad revision: 4f1383af8f10 (2008-11-01)
Depends on: 895096


3 years ago
Duplicate of this bug: 419083


3 years ago
Duplicate of this bug: 1046390

Comment 18

3 years ago
This appears to still be an issue. Very annoying not being able to zoom out without rendering the page incorrectly.
Duplicate of this bug: 1227125
Duplicate of this bug: 1140271


2 years ago
Duplicate of this bug: 986537

Comment 22

a year ago
Is this bug ever going to be fixed? You know it's bad when IE can avoid this.

Comment 23

a year ago
Firefox 47 - Windows 10

Now firefox depends of Windows display property, Great.

This property default value is 125% on Windows 10 (at least on 1920x1080).
So if you are using firefox, 100% zoom in firefox = 125% for all websites.
If you have html tables in an app/website, sometimes border disappear, sometimes it's normal, sometimes it's thicker. And you know what ? If you scroll, border width will change dynamically !

This bug has been reported in 2008. eight years ago.

Comment 24

7 months ago
Firefox 50.0.2 Windows 7

Button element with a solid border (color or transparent) comprised of a gradient background such as "background: -moz-linear-gradient(top, #333"  #000)" will display borders that are colored opposite the start/end color of adjacent button gradient, at any browser zoom factor.

Button element with no borders (none) or with borders of 0px width do not display the above-mentioned defects where gradients are used.

Comment 25

3 months ago
Well, since the Firefox official won't fix it, I do a workaround:
Write this in your user styles:

@-moz-document url-prefix() { /* Firefox only */
	table {
		border-collapse: separate !important;
		border-spacing: 0px;
	tr:not(:last-child) th, tr:not(:last-child) td {
		border-bottom-width: 0 !important;
	th:not(:last-child), td:not(:last-child) {
		border-right-width: 0 !important;

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