627043 - Tabs disappear when opening/closing new tab or selecting different tab, sometimes permanently

Status: RESOLVED DUPLICATE of bug 623852

(Firefox :: General, defect)

Description

[Greg]

User-Agent:       Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0b9) Gecko/20100101 Firefox/4.0b9
Build Identifier: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0b9) Gecko/20100101 Firefox/4.0b9

Whenever a change to the tabs occurs -- from opening/closing a tab or scrolling to other tabs -- the tabs disappear and take a long time (~15 - 30 seconds) to become visible again, unless the mouse is moved over the tabs, restoring the visibility of the tab under the mouse. Sometimes (~1 in 20 times changing the tabs bar) the tabs never become visible again and cannot be selected, requiring a restart. Also, the top "line" of firefox (directly above the tabs, contains the close/maximize/minimize buttons and the website name) flickers when typing or scrolling. Neither of these occured in any of the previous versions of Firefox (3.6.x as well as 4b6, 4b7, or 4b8), nor do they occur in Firefox 4b9 under Windows XP or Windows 7 Ultimate x64. Opening the Add-ons page also suffers from the effect, with all of the elements not appearing until moused over (see http://tinypic.com/r/w8qhxw/7 ).

Reproducible: Always

Steps to Reproduce:
1. Preferably use a 2006 Macbook Pro (version 1,1) with a 2.0ghz Core Duo, 2048mb ram (500+ mb free, not a page file/swap problem - no pages occuring), and a Radeon mobility X1600 gpu with 128mb GDDR3 memory running on OS X 10.6.6 with all software/firmware updates applied.
2. Do anything that changes the on screen appearance of the tabs bar.
3. Alternatively, open the Add-ons page.

Actual Results:  
Tabs disappear as described in the summary.

Expected Results:  
The tabs should remain visible and the top bar should not flicker.

System:
Macbook Pro version 1,1 (late 2006)
2.0 ghz Core Duo
2048 mb DDR2 Ram @ 533mhz
320 gb 5400 rpm HDD
Radeon Mobility X1600 w/ 128 mb GDDR3 ram
OS X 10.6.6 Snow Leopard

Firefox 4b9
Add-ons enabled:
Adblock Plus 1.3.3
Add-on Compatibility Reporter 0.7
Autopager 0.6.2.0
Craigslist Peek 0.520
Feedback 1.0.3
Flash Video Downloader 2.0.16
Lastpass 1.70.0
Read It Later 2.1.1
Session Manager 0.6.9.3
Stylish 1.0.11 (Compatibility mode - only used on one forum)

Comment 1

[Markus Stange [:mstange]]

The fix for this bug unfortunately didn't make it into Beta 9. The bug will be fixed in Beta 10.