426811 - Doubleclicking tab bar arrows scrolls one tab too far.

Status: NEW

(Firefox :: Tabbed Browser, defect)

Description

[Roscoe Primrose]

User-Agent:       Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9b5) Gecko/2008032619 Firefox/3.0b5
Build Identifier: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9b5) Gecko/2008032619 Firefox/3.0b5

If you doubleclick on the left or right tab bar arrows to scroll left or right one window's worth of tabs, you scroll left/right one tab on the first click, then an entire window's worth on the second tab.  This leaves the tab that was originally one tab off-screen to the right/left now one tab off-screen to the left/right, rather than being the left/right-most tab as it should be.

Reproducible: Always

Steps to Reproduce:
1.Have enough tabs open to have several windows worth
2.double-click left or right tab bar arrow
3.
Actual Results:  
tabs scroll one more than a window's worth left or right

Expected Results:  
tabs should scroll one window's worth left or right.

This is not a new problem with beta 5

Comment 1

[Bob Uliss]

Mozilla/5.0 (Macintosh; U; PPC Mac OS X 10.5; en-US; rv:1.9pre) Gecko/2008042904 Minefield/3.0pre
Confirmed in this build

Comment 2

[Tyler Downer [He/Him]]

This bug was reported using Firefox 3.0 or older, which is no longer supported. The bug has also not been changed in over 500 days and is still in UNCO.
Reporter, please retest this bug in Firefox 3.6.10 or later using a fresh profile, http://support.mozilla.com/en-US/kb/managing+profiles. If you still see this problem, please update the bug. If you no longer see the bug, please set the resolution to RESOLVED, WORKSFORME.

This is a mass search of unconfirmed bugs that have no activity on them, so if you feel a bug was marked in error, just remove the CLOSEME comment in the whiteboard within the next month.

Comment 3

[Roscoe Primrose]

Still seeing same behavior in a new, clean profile with Minefield 4.0b8pre on XP...

Comment 4

[Roscoe Primrose]

Also seeing in Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:2.0b6) Gecko/20100101 Firefox/4.0b6

Comment 5

[star]

Can confirm this bug in recent Firefox 11 (Win7). 

This is a real nasty bug. The tab-list is scrolled at least one tab to far by doubleclick the scrollbar arrows. 
This bug is insided since version 3 or earlier. 
Please, please fix this!!
It is independent on the screen size. If you can't verify this: My settings are no menu, navigation tabs visible, tabs on top.

Comment 6

[Charles Belov]

Can confirm this bug in Firefox 108.0.1 (64-bit) in macOS 13.1.

I have around 50 or so tabs I need to review on a daily basis, and smooth scrolling bothers me, so this is an accessibility issue for me.

Steps:
For the following home page (this isn't my daily review set - this is an occasional set - but it's easiest to see the issue):

https://www.sfmta.com/1|https://www.sfmta.com/1AX|https://www.sfmta.com/1BX|https://www.sfmta.com/2|https://www.sfmta.com/3|https://www.sfmta.com/5|https://www.sfmta.com/5R|https://www.sfmta.com/6|https://www.sfmta.com/7|https://www.sfmta.com/7X|https://www.sfmta.com/8|https://www.sfmta.com/8AX|https://www.sfmta.com/8BX|https://www.sfmta.com/9|https://www.sfmta.com/9R|https://www.sfmta.com/12|https://www.sfmta.com/14|https://www.sfmta.com/14R|https://www.sfmta.com/14X|https://www.sfmta.com/15|https://www.sfmta.com/18|https://www.sfmta.com/19|https://www.sfmta.com/21|https://www.sfmta.com/22|https://www.sfmta.com/23|https://www.sfmta.com/24|https://www.sfmta.com/25|https://www.sfmta.com/27|https://www.sfmta.com/28|https://www.sfmta.com/28R|https://www.sfmta.com/29|https://www.sfmta.com/30|https://www.sfmta.com/30X|https://www.sfmta.com/31|https://www.sfmta.com/31AX|https://www.sfmta.com/31BX|https://www.sfmta.com/33|https://www.sfmta.com/35|https://www.sfmta.com/36|https://www.sfmta.com/37|https://www.sfmta.com/38|https://www.sfmta.com/38R|https://www.sfmta.com/38AX|https://www.sfmta.com/38BX|https://www.sfmta.com/39|https://www.sfmta.com/41|https://www.sfmta.com/43|https://www.sfmta.com/44|https://www.sfmta.com/45|https://www.sfmta.com/48|https://www.sfmta.com/49|https://www.sfmta.com/52|https://www.sfmta.com/54|https://www.sfmta.com/55|https://www.sfmta.com/56|https://www.sfmta.com/57|https://www.sfmta.com/58|https://www.sfmta.com/66|https://www.sfmta.com/67|https://www.sfmta.com/76X|https://www.sfmta.com/81X|https://www.sfmta.com/82X|https://www.sfmta.com/90|https://www.sfmta.com/91|https://www.sfmta.com/714|https://www.sfmta.com/C|https://www.sfmta.com/CA|https://www.sfmta.com/PH|https://www.sfmta.com/PM|https://www.sfmta.com/E|https://www.sfmta.com/F|https://www.sfmta.com/J|https://www.sfmta.com/JBUS|https://www.sfmta.com/K|https://www.sfmta.com/KBUS|https://www.sfmta.com/KT|https://www.sfmta.com/L|https://www.sfmta.com/LBUS|https://www.sfmta.com/LSP|https://www.sfmta.com/LOWL|https://www.sfmta.com/M|https://www.sfmta.com/MBUS|https://www.sfmta.com/N|https://www.sfmta.com/NBUS|https://www.sfmta.com/NOWL|https://www.sfmta.com/S|https://www.sfmta.com/T|https://www.sfmta.com/TBUS

1. Launch Firefox
2. Wait for the pages to load
3. Adjust your browser width such that the last tab displayed is for route 9
4. Double-click the right-pointing chevron at the right of the tab list

Expected result: Route 9 is now the left-hand tab. Immediately to the right of it is the tab for route 9R.
Actual result: Route 12 is now the left-hand tab. We have completely skipped over the tab for route 9R.

5. Single-click the left-pointing chevron at the left of the tab list to reveal 9R.
6. Note that the last tab displayed is now route 27.
7. Double-click the right-pointing chevron at the right of the tab list

Expected result: Route 27 is now the left-hand tab. Immediately to the right of it is the tab for route 28.
Actual result: Route 29 is now the left-hand tab. We have completely skipped over the tab for routes 28 and 28R and I have to click on the left-pointing chevron to reveal them. If I click a second time too soon (not sure how soon too soon is but I didn't perceive what I was doing as a double-click) it does a super-scroll and route 28 is at the right, where I would expect a double-click from route 29 at the left to leave route 29 at the right.