1387171 - Tabbar scrolls when exiting customize mode

Status: VERIFIED FIXED

(Firefox :: Theme, defect, P1)

Description

[Oriol Brufau [:Oriol]]

1. Use Ctrl+T to create lots of tabs so that the tabbar overflows
2. Click Customize in hamburger menu
3. Click some tab other than the customizing one

Result: the tabbar scrolls so that the clicked tab appears at the right side of the tabbar.

Expected: the tabbar should not scroll.

Pushlog: https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=ecbeb9354c24bac41419cfbd71ce107f86ea4619&tochange=975e4a8c3e3e83af2ac54fa3691861f79186b48f

Comment 2

[Dale Harvey (:daleharvey)]

Ill try seeing whats up with this

Comment 3

[Dale Harvey (:daleharvey)]

Bisecting and looks caused by https://reviewboard.mozilla.org/r/163888/diff/3#index_header

Comment 4

[Dale Harvey (:daleharvey)]

Attachment: Bug 1387171 - Prevent tabs scrolling when enter / leaving customise move.

Review commit: https://reviewboard.mozilla.org/r/182926/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/182926/

Comment 5

[Dale Harvey (:daleharvey)]

The change in display property for some reason causes the tab bar to scroll, confusing behaviour for me and seem like it may be a flexbox bug since I cant seen anything from js causing this, but I spent way too long looking and Justin said to not get stuck down obscure rabbit holes, making the border transparent or 0px doesnt cause the reflow + scroll

Comment 6

[Dão Gottwald [:dao]]

Comment on attachment 8911457 [details]
Bug 1387171 - Prevent tabs scrolling when enter / leaving customise move.

https://reviewboard.mozilla.org/r/182926/#review188142

::: browser/themes/shared/browser.inc.css:39
(Diff revision 1)
>    display: -moz-box;
>    border-bottom: 1px solid var(--toolbox-border-bottom-color);
>  }
>  
>  :root[customizing] #navigator-toolbox::after {
> -  display: none;
> +  border-bottom: 0px;

Please use border-bottom-style: none. Thanks!

Comment 7

[Dale Harvey (:daleharvey)]

Comment on attachment 8911457 [details]
Bug 1387171 - Prevent tabs scrolling when enter / leaving customise move.

Review request updated; see interdiff: https://reviewboard.mozilla.org/r/182926/diff/1-2/

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/8a1fb4e24d18
Prevent tabs scrolling when enter / leaving customise move. r=dao

Comment 9

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/8a1fb4e24d18

Comment 10

[Dale Harvey (:daleharvey)]

Comment on attachment 8911457 [details]
Bug 1387171 - Prevent tabs scrolling when enter / leaving customise move.

Approval Request Comment
[Feature/Bug causing the regression]: Initial implementation of photon tabs (https://bugzilla.mozilla.org/show_bug.cgi?id=1349555)
[User impact if declined]: Confusing behaviour of scrolling tabs when entering / leaving customise mode
[Is this code covered by automated tests?]: no
[Has the fix been verified in Nightly?]: not yet
[Needs manual test from QE? If yes, steps to reproduce]: make a lot of tabs, then enter / leave customise mode 
[List of other uplifts needed for the feature/fix]:
[Is the change risky?]:
[Why is the change risky/not risky?]:
[String changes made/needed]:

Comment 11

[Itiel]

Looking good on latest Nightly.

Comment 12

[Sylvestre Ledru [:Sylvestre]]

Dale, next time, please fill the following information, they are key for release manager and QE:
[Is the change risky?]:
[Why is the change risky/not risky?]:

Comment 13

[Dale Harvey (:daleharvey)]

Comment on attachment 8911457 [details]
Bug 1387171 - Prevent tabs scrolling when enter / leaving customise move.

[Feature/Bug causing the regression]: Initial implementation of photon tabs (https://bugzilla.mozilla.org/show_bug.cgi?id=1349555)
[User impact if declined]: Confusing behaviour of scrolling tabs when entering / leaving customise mode
[Is this code covered by automated tests?]: no
[Has the fix been verified in Nightly?]: not yet
[Needs manual test from QE? If yes, steps to reproduce]: make a lot of tabs, then enter / leave customise mode 
[List of other uplifts needed for the feature/fix]:
[Is the change risky?]: Nope
[Why is the change risky/not risky?]: Minor CSS change
[String changes made/needed]:

Comment 14

[Sylvestre Ledru [:Sylvestre]]

Comment on attachment 8911457 [details]
Bug 1387171 - Prevent tabs scrolling when enter / leaving customise move.

Polish photon, taking it.
Should be in 57b4. GTB later today.

Comment 15

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/releases/mozilla-beta/rev/cda60381e179

Comment 16

[Emil Ghitta, QA [:emilghitta]]

I have managed to reproduce this issue using Firefox 57.0a1 (BuildId:20170803134456) by following the steps mentioned in comment 0. 
This issue is verified fixed on Firefox 57.0b6 (BuildId:20171005195903) using Windows 10 64bit macOS 10.11.6 and Ubuntu 16.04 64bit.