1988233 - Vertical tab panel does not shrink when mouse switches windows

Status: RESOLVED DUPLICATE of bug 1985692

(Firefox :: Sidebar, defect)

Description

[TA]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:142.0) Gecko/20100101 Firefox/142.0

Steps to reproduce:

1. Enable vertical tabs, and set to auto expand on hover
2. Have Firefox in a place with space to move the mouse directly from the vertical tab panel into. For example:
3. a. Firefox on the right side of a screen, with space empty on the left
4. b. Firefox on a right monitor, with another monitor on the left
5. c. Windows taskbar visible under Firefox
6. Move the mouse quickly over the vertical tab bar, to the relevant empty space:
7. a. Outside the Firefox window, directly on the left
8. b. To the other monitor
9. c. To the vertical tab panel, and directly down to the taskbar

Additionally, this also happens when entering the Firefox window over the bar area quickly from the side (but not from the taskbar).

In cases "a" and "b", it has to be a quick motion. It does not happen when waiting for a second for the panel to expand.

In case "c", waiting does not alleviate the issue.

Actual results:

The vertical tabs panel stays open.

Expected results:

The vertical tabs panel should shrink.

Comment 1

[BugBot [:suhaib / :marco]]

The Bugbug bot thinks this bug should belong to the 'Firefox::Sidebar' component, and is moving the bug to that component. Please correct in case you think the bot is wrong.

Comment 2

[Monica Chiorean (OOO July 31st 5:30PM)]

This issue is similar with bug 1988384. But I am not able to reproduce this on Win11x64 using FF build 142.0.1.
TA, does this issue reproduce with a new and empty profile? See https://support.mozilla.org/en-US/kb/troubleshoot-and-diagnose-firefox-problems#w_6-create-a-new-firefox-profile
Thank you.

Comment 3

[TA]

Reproduces for me on a new and empty profile on build 142.0.1 on Win11x64.

On my work PC which has the ESR version, just going over the panel into or out of the window doesn't keep it open. However panel to taskbar, does reproduce - I feel these are different issues.

Any other information I can give?

Comment 4

[TA]

I tried again with a new Firefox installer in Windows Sandbox, in order to avoid any loose configurations - Same thing.

Maybe it's something to do with hardware/drivers? Multiple monitors? Resolution? Refresh rate?

Both of my monitors have high refresh rates, 240hz and 144hz. I have an NVidia GPU with G-Sync enabled "in full-screen and windowed".

I think an important clue is that it only happens if I move my mouse quickly over the bar. If I move it slowly, or stop on the bar for a second, it closes correctly. Maybe some sort of debouncing, or missed inputs?