1925451 - Tabs disappearing (vertical tabs)

Status: VERIFIED FIXED

(Firefox :: Sidebar, defect, P1)

Description

[Nils]

Attachment: Scherm­afbeelding 2024-10-18 om 09.00.52.png

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:133.0) Gecko/20100101 Firefox/133.0

Steps to reproduce:

Moved a tab from one monitor to another monitor.

Actual results:

The tabs in the vertical tabs column disappeared. I can still open a new tab in this windows through the shortcut, but no tabs are visible.

This usually happens after my Macbook has been in sleep, for example the next workday.

Expected results:

The tabs should have been visible.

Comment 1

[Nils]

I can now constantly reproduce this by dragging a tab from one monitor to another. It always has the tab disappearing in the new window.

Comment 2

[Sarah Clements [:sclements]]

Hi, the STR could use more clarity, ie what's happening in the browser window in monitor 1 vs monitor 2. Do you initially see all of the tabs on monitor 1, and then do you wait for the tab to fully load before dragging it to the other monitor?

Are you trying to drag it to a new window in monitor 2 or into an existing window? Would also be helpful to confirm this not happening on latest Nightly (133.0a1) and its not something that happens with horizontal tabs.

Comment 3

[Nils]

Attachment: Schermopname 2024-10-18 om 13.59.29.mov

Comment 4

[Nils]

It's actually a good point. As soon as I drag a tab out of the sidebar and let go, the new window appears and nothing in the sidebar is visible.

I've made a screen recording of this and attached this to the bug so you can see what is happening visually. This is the same method I use to drag it to my second monitor.

Comment 5

[Stuart Colville [:muffinresearch]]

Hi, as per the question in comment 2, please could you confirm if this happens with horizontal tabs or is it just vertical?

Additionally, to rule out add-ons/extensions, does this reproduce if you restart in trouble-shoot mode? https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode

Comment 6

[Nils]

Okay so it's a bit harder to reproduce than I first thought. I updated Firefox and the bug was gone. I've just now encountered it on Windows 11 as well. Dragged a tab out and the sidebar was completely empty. Went into the settings and disabled the sidebar and all tabs appeared at the top. Enabled the sidebar with vertical tabs and the issue is gone again.

Tried on my Mac during the weekend to reproduce, but couldn't. At this point I am unsure what is causing the bug.

Comment 7

[Kelly Cochrane [:kcochrane]]

I was just able to reproduce this by opening a google document from a google calendar event and then dragging the tab over from my external monitor to my laptop's screen. I'm not able to reproduce it now though, and didn't get a chance to open the Browser Toolbox to see if there were any relevant errors.

Comment 8

[Gabi Cheta [:Gabi] Desktop QA]

Attachment: Screenshot 2024-10-24 at 11.06.27.jpg

Comment 9

[Gabi Cheta [:Gabi] Desktop QA]

I managed to reproduce the issue just once on a MacBook Pro macOS 14 laptop by dragging a google document into a new window.
No luck in reproducing the bug using a multi monitor Win 10 x64 laptop.
We will keep an eye out for the issue and keep trying to reproduce while testing the sidebar.

Comment 10

[Stuart Colville [:muffinresearch]]

(In reply to Gabi Cheta [:Gabi] Desktop QA from comment #9)

I managed to reproduce the issue just once on a MacBook Pro macOS 14 laptop by dragging a google document into a new window.
No luck in reproducing the bug using a multi monitor Win 10 x64 laptop.
We will keep an eye out for the issue and keep trying to reproduce while testing the sidebar.

Thanks for checking. One thing that would be useful would be to know is if there's anything recorded in the browser console when this happens in-case there's an exception that would help us understand the root cause.

Comment 11

[Nils]

I've got an instance of Firefox Nightly on my Macbook at this moment that is bugged. What steps would you like me to take? I've checked the F12 console and it is completely empty.
Please note that as soon as I close the program entirely or install an update, the issue disappears for a while.

Comment 12

[Stuart Colville [:muffinresearch]]

(In reply to Nils from comment #11)

I've got an instance of Firefox Nightly on my Macbook at this moment that is bugged. What steps would you like me to take? I've checked the F12 console and it is completely empty.
Please note that as soon as I close the program entirely or install an update, the issue disappears for a while.

This doc has some details about how to open the browser console (as opposed to the web console) https://firefox-source-docs.mozilla.org/devtools-user/browser_console/index.html

Comment 13

[Nils]

Attachment: Scherm­afbeelding 2024-10-24 om 16.26.34.png

Console was open while a tab was dragged out of the sidebar and a new window appeared with an empty sidebar.

Comment 14

[Sarah Clements [:sclements]]

Thanks for that - I'm still having a hard time reproducing.

Dao, Mike - any inkling of what could be going on? The console image shows a "groupId" - any chance that is related to tab groups code? Likely a red herring but there's not much else to go on at the moment.

Comment 15

[Mike Conley (:mconley) (:⚙️)]

This has all of the indications of some kind of race. I'd be curious if people in the buggy state could inspect the empty sidebar with the Browser Toolbox to determine whether:

1. The DOM in the sidebar is empty, and that's why we're not rendering anything
2. The DOM in the sidebar has what's expected, but for some reason, it's being hidden / not rendered

Comment 16

[Nils]

If you can tell me how I can inspect it with the Browser Toolbox, I'd be willing to do so. I won't be closing or updating the browser for now, which means I am staying in bugged state.

Comment 17

[Mike Conley (:mconley) (:⚙️)]

Hey Nils,

I appreciate your willingness to help us out and investigate!

In order to open the Browser Toolbox, you're going to need to flip some preferences in the DevTools settings UI. Instructions are here: https://firefox-source-docs.mozilla.org/devtools-user/browser_toolbox/index.html

After you do that, you should have the ability (via the AppMenu > More Tools) menu to open the Browser Toolbox. A connection warning window might appear after you open that, and you can go ahead and confirm the connection (since it's yourself connecting the toolbox to your browser).

After that, one of the items in the DevTools panel will be "Inspector". To the left of that is an icon with a 3/4 square and a mouse cursor inside of it. If you click that latter button in the Browser Toolbox, you can then switch to the Firefox window with the buggy sidebar, and then click the sidebar. Hopefully, the markup that defines the sidebar will appear in the Inspector pane when you do that. I'd love to see a screenshot of that Inspector pane in such a state.

Comment 18

[Sarah Clements [:sclements]]

So the tabstrip could be toggled either by this event firing "tabstrip-orientation-change" from CUI code when the vertical tabs pref is flipped or as part of the init function but which is gated on CUI. So perhaps something is racy there specifically when a new window via tab drag(?) occurs.

Comment 19

[Gabi Cheta [:Gabi] Desktop QA]

Attachment: 2024-10-25_12h16_50.mp4

Comment 20

[Gabi Cheta [:Gabi] Desktop QA]

I've found a way to reproduce the tab disappearing issue by installing and removing the Tree Style Tab add-on before dragging a tab to a new window.
At this point I'm not sure if it's the same issue since I was able to reproduce it once without having any add-on installed, maybe it helps with the base issue.
I'm attaching a recording with the steps.

Comment 21

[Nils]

Attachment: Scherm­afbeelding 2024-10-25 om 13.35.28.png

Here's the screenshot of the inspector pane after clicking the sidebar. Let me know if you need anything more.

I'm also going to add to this that I did update Firefox Nightly this morning and as such was no longer in a bugged state. It didn't take long to be back in the bugged state. During this time I did not add or remove any extensions.

Comment 22

[Kelly Cochrane [:kcochrane]]

:Gabi that worked for me, I was able to repro just now. Thanks so much, I'm taking a look now!
And thanks for the screenshot, :Nils!

Comment 23

[Kelly Cochrane [:kcochrane]]

It looks like it's reproducible after simply selecting and closing multiple tabs. Installing/removing the extension isn't necessary.

Comment 24

[Philip Luk [:pluk]]

I hit a potentially similar situation. What I did was drag a tab to a second window and created a new tab on the second window. Upon creation of the new tab, all of the vertical tabs disappeared on the second window (even though through FxView I could still see Window 2 had multiple tabs open). Vertical Tabs on the first window still work fine. If I open a third window, now it starts off also with zero vertical tabs.

Looking at the console output, this seemed suspicious..

"Empty string passed to getElementById(). 2 335150757-waffle_js_prod_integrated_core.js:1921:147"

Let me know what else I can share to help debug?

Comment 25

[Kelly Cochrane [:kcochrane]]

Just ran this through moz-regression, and it seems to point to changes in bug 1899598 as the regressor.

Comment 26

[Kelly Cochrane [:kcochrane]]

Attachment: Bug 1925451 - Fix for vertical tabs not always being visible in new windows

Comment 27

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/476ed7d837d8
Fix for vertical tabs not always being visible in new windows r=sidebar-reviewers,Gijs,sclements

Comment 28

[Kelly Cochrane [:kcochrane]]

Comment on attachment 9433755 [details]
Bug 1925451 - Fix for vertical tabs not always being visible in new windows

Beta/Release Uplift Approval Request

• User impact if declined/Reason for urgency: After opening a popup, vertical tabs can be missing from new windows
• Is this code covered by automated tests?: Yes
• Has the fix been verified in Nightly?: Yes
• Needs manual test from QE?: Yes
• If yes, steps to reproduce: enabling vertical tabs, installing the Tree Style Tabs add-on, opening a few new tabs, closing at least 2 of those tabs by selecting them and using the context menu to “Close selected tabs”. That should trigger a popup to confirm you want to close the selected tabs. Select “Close tabs” in this popup, then either open a new tab and drag it to its own window or simply open a new browser window. That new window will not display the vertical tab in the sidebar (although it will still show in TST).
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): Only changes 2 lines of code to ensure we're applying the same CUI transformation to all vertical tabs windows rather than excluding popups as this can lead to a blank saved state in CUI.
• String changes made/needed:
• Is Android affected?: No

Comment 29

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/476ed7d837d8

Comment 30

[Gabi Cheta [:Gabi] Desktop QA]

Verified as fixed in Firefox Nightly 134.0a1(2024-10-30) Windows 10x64, macOS 14 and Ubuntu 24.0.

Comment 31

[Donal Meehan [:dmeehan]]

Comment on attachment 9433755 [details]
Bug 1925451 - Fix for vertical tabs not always being visible in new windows

Approved for 133.0b3

Comment 32

[Pulsebot]

https://hg.mozilla.org/releases/mozilla-beta/rev/8012edf5607b

Comment 33

[Gabi Cheta [:Gabi] Desktop QA]

Verified as fixed in Firefox 133.0b3 treeherder build Windows 10x64, macOS 14 and Ubuntu 24.0.