469139 - Keyboard scrolling fails after switching between loading tabs

Status: RESOLVED FIXED

(Firefox :: Keyboard Navigation, defect)

Description

[kmike]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; rv:1.9.1b3pre) Gecko/20081208 SeaMonkey/2.0a3pre
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.4) Gecko/2008102920 Firefox/3.0.4

I'm an avid keyboard user, and this bug has been plaguing me since the times of Mozilla 1.x, so I've already grew accustomed to clicking on a newly loaded page first to regain the keyboard focus.
But I thought it's time to lose that bad habit so I spent some time today to find a 100% reproducible chain of events leading to the loss of keyboard focus.


Reproducible: Always

Steps to Reproduce:
1. Open a new window, load any page, for example http://www.mozilla.org

2. Open a second tab with CTRL-T (focus should be in the location bar), type forums.mozillazine.org and press ENTER, wait for the page to load. Check that the keyboard scrolling works.

3. Click on the "Firefox Support" forum link (we need a slow enough page here, a forum thread list works wonders)

4. Quickly press CTRL-PageUp to switch to the first tab while the "Firefox Support" page still loads.

5. Wait until the "Firefox Support" forum page finishes loading in the background tab.

6. Press "CTRL-PageDown" to switch back to the second tab with Firefox Support forum.

Actual Results:  
Observe that scrolling with the keyboard doesn't work in the second tab. In particular, the arrow keys and Home/End/PageUp/PageDown/Space keys do not scroll the page as they should. 


Expected Results:  
Keyboard scrolling should work.

Other keyboard commands such as CTRL-F, CTRL-W, CTRL-Left & CTRL-Right still work.
You can press CTRL-Tab to switch between the tabs instead of CTRL-PageUp/Down, the results will be the same.

Note that normally I use Seamonkey but this bug also affects Firefox 3.0.4 so I'm filing it against Firefox.

Comment 1

[kmike]

Still happens in Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.6) Gecko/2009011912 Firefox/3.0.6

Comment 2

[Steve England [:stevee]]

Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2a1pre) Gecko/20090223 Minefield/3.2a1pre
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1b3pre) Gecko/20090223 Shiretoko/3.1b3pre ID:20090223034549

I see this bug on the trunk and branch, but both myself and kmike are unable to reproduce it with Steven Michaud's tryserver build that has the new focus rewrite code included (bug 178324 comment 78):
- https://build.mozilla.org/tryserver-builds/2009-02-20_12:[e-mail]-bugzilla178324-feb13-enndeakin/

So confirming setting to bug 83552.