965640 - new tabs being placed in incorrect positions in Tab App Bar (sometimes browser becoming unstable)

Status: RESOLVED INCOMPLETE

(Firefox for Metro Graveyard :: App Bar, defect)

Description

[Kamil Jozwiak [:kjozwiak]]

Attachment: incorrectTabPosition1.jpg

You can get into a situation were newly created tabs will be placed in the incorrect positions in the Tab App Bar. This usually happens when you close a few tabs very quickly while they are loading. I've ran into this a few times and reproduced it on both Nightly & Aurora. Once this happens, if you close all the remaining tabs, the browser can sometimes become unstable.

- Attached a few screenshots to illustrate the issue

Steps to reproduce the issue:

1) Open Firefox Metro
2) Type in a website in the URL that takes a while to load and quickly press CTRL + T and start loading another website (using a keyboard is best)
3) Do Step #2 a few times very quickly so you have three websites opened and loading
4) Very quickly slide in the Tap App Bar and close all the tabs by taping on the "X" of each tab
5) You'll notice that the new about:start tab will slide into the Tab App Bar were the third tab used to be (sometimes if you close this tab the browser becomes unstable and very hard to use)

Current Behaviour:

- When you create new tabs very quickly and then close them really fast, you'll get into a situation were the new tabs will be positioned incorrectly in the Tab App Bar. Closing these tabs makes the browser unstable at times.

Expected Behaviour:

- Tabs should slide into the FIRST position and not into the position were the last tab used to be. Closing tabs shouldn't cause any stability issues with the browser

Found the issue using the following builds:
- http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/2014-01-29-00-40-17-mozilla-aurora/
- http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/2014-01-29-03-06-02-mozilla-central/

Comment 1

[Kamil Jozwiak [:kjozwiak]]

Attachment: incorrectTabPosition2.jpg

Comment 2

[Kamil Jozwiak [:kjozwiak]]

Attachment: blankBrowserUnstable.jpg

Comment 3

[Kamil Jozwiak [:kjozwiak]]

I think this should probably be looked at in the near future. I am running into this more and more, especially when I'm dogfooding at night when I'm checking emails etc.. Sometimes I'll create an extra tab or I open a tab that I don't want and I quickly dismiss it before it can finish loading which results in the issue mentioned on comment #0.

Its not the easiest to reproduce, but when it happens and someone closes all their tabs, the browser basically becomes unusable until its completely restarted.

Comment 4

[Firefox Bug Husbandry Bot]

Mass close of bugs in obsolete product https://bugzilla.mozilla.org/show_bug.cgi?id=1350354