Persistent Ghost Tabs appear on Windows' Taskbar with dual displays

[Stef-UK]

Environment:

• Firefox: 137.0.2
• Windows 11 Version 24H2 (OS Build: 26.100.3775), Experience Pack: 1000.26100.66.0
• Windows Settings:
•     Dual monitors present.  System > Display > Extend these displays
•     Personalisation > TaskBar - Taskbar Behaviours - Show my taskbar on all displays = ON

Bug (1):

• Start with  "Show my taskbar..." setting OFF, and Firefox active on 2nd display only, 3 open tabs.
• Enable the  "Show my taskbar..." setting via Windows settings
• Hover the cursor over the FF icon on the 2nd display's taskbar.  You will see duplication (2x3) open icons appear above the taskbar (PIC-1.jpg).

Bug (2):

• Start with  "Show my taskbar..." setting ON, and Firefox active on 2nd display only, 3 open tabs.
• Close one or two FF tabs and hover the cursor over the FF icon on the 2nd display's taskbar. You will see 'ghost' icon(s) representing the closed tab(s). (PIC-2.jpg).

Effects

1. Such 'ghosts' do not disappear, even if you close and re-open Firefox.
2. They do not appear if you hover the cursor over the Firefox icon on the taskbar of the primary display
3. They do not appear if you turn OFF the "Show my taskbar..." setting via Windows settings.

[L3x]

Yes, unfortunately, this bug really annoys me too.
Only on Windows 11 and currently affects two applications (Mozilla Firefox + Adobe Reader).

I use three monitors.
If you open Firefox on one screen and drag it to another, multiple tabs appear in the taskbar.
If you drag Firefox back to the main screen, it works, and it's stacked - correct.

The only solution so far has been to close and reopen the browser.

As I said, it only affects the two software solutions so far.
I hope either Microsoft, or more likely Mozilla and Adobe, can fix this.

[dds]

I'm experiencing the same issue with Firefox. I'm using two monitors, and even though I keep all the windows on the same monitor, ghost windows still appear.

[DarioViva]

It's even worse when items in taskbar also show their title.
Bug on Bugzilla: https://bugzilla.mozilla.org/show_bug.cgi?id=1986589

[Tri4L]

Same problem here, tab display bug on dual monitor.
Firefox 143.0.1 
Win11 24h2

[Mars_chroma]

Also having this issue.

Firefox 143.0.4 and I'm sure at least one previous version.

It only started recently for me, and so far firefox seems to be the only application that does it.

Windows 11 24h2

[Mars_chroma]

Restarting Windows Explorer fixes the issue temporarily until another ghost window pops up, if that helps.

Edit: I am now on Firefox 144.0 and the issue is still present.
GPU: NVIDIA GeForce RTX 3070 TI, Studio Driver 581.57 (issue was present on the previous driver release as well on Windows 11).

[RickJamesLR]

If anyone else is having this issue on windows 11 24h2, i  found a solution that worked for me, I unpinned my firefox app on the taskbar that would open a new instance of firefox next to my pinned one. I then opened firefox from the install location and pinned the tab that showed up from doing that, it seems to now stack now and doesnt open any new tabs next to the new pinned one. they now all stack neatly on the new pinned icon on the taskbar.