https://support.mozilla.org/en-US/kb/update-firefox-latest-version 38.0.5

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

While still in Safe Mode,

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP in front of the numbers/letters, click it and select Submit.

Using your mouse, mark the most resent 7 - 10 crash reports, and copy them. Now go to the reply box below and paste them in.

I have updated my firefox to latest version i.e. 38.0.5. I started firefox with parameter -safe-mode . Firefox started in safe mode. I was able to dock it inside my wpf window as described earlier. Now I did a control click on one of the link on www.bing.com . Firefox crashed again .

I started firefox again manually while holding shift and typed in about:crashes. There were only 2 entries [with bp in front] that i had already submitted earlier when i first encountered this problem . Surprisingly i can see only those crash reports that i have submitted to firefox already.

For your reference i have manually captured these details after each crash : Attempt 1 : AdapterDeviceID: 0x0166 AdapterDriverVersion: 9.18.10.3165 AdapterSubsysID: 00000000 AdapterVendorID: 0x8086 AvailablePageFile: 8217464832 AvailablePhysicalMemory: 2414489600 AvailableVirtualMemory: 3907043328 BIOS_Manufacturer: American Megatrends Inc. BlockedDllList: BreakpadReserveAddress: 44302336 BreakpadReserveSize: 67108864 BuildID: 20150525141253 CrashTime: 1434987651 EMCheckCompatibility: true Email: Nfactor26@gmail.com EventLoopNestingLevel: 1 FramePoisonBase: 00000000f0de0000 FramePoisonSize: 65536 InstallTime: 1434878680 Notes: AdapterVendorID: 0x8086, AdapterDeviceID: 0x0166, AdapterSubsysID: 00000000, AdapterDriverVersion: 9.18.10.3165 Has dual GPUs. GPU #2: AdapterVendorID2: 0x10de, AdapterDeviceID2: 0x0fd1, AdapterSubsysID2: 00000000, AdapterDriverVersion2: 9.18.13.5012 ProductID: {ec8030f7-c20a-464f-9b0e-13a3a9e97384} ProductName: Firefox ReleaseChannel: release SecondsSinceLastCrash: 449 StartupTime: 1434987635 SystemMemoryUsePercentage: 61 Theme: classic/1.0 Throttleable: 1 TotalPageFile: 12667805696 TotalPhysicalMemory: 6334840832 TotalVirtualMemory: 4294836224 URL: http://www.bing.com/ Vendor: Mozilla Version: 38.0.5 Winsock_LSP: MSAFD Tcpip [TCP/IP] : 2 : 1 : %SystemRoot%\system32\mswsock.dll

MSAFD Tcpip [UDP/IP] : 2 : 2 :  
MSAFD Tcpip [RAW/IP] : 2 : 3 : %SystemRoot%\system32\mswsock.dll 
MSAFD Tcpip [TCP/IPv6] : 2 : 1 :  
MSAFD Tcpip [UDP/IPv6] : 2 : 2 : %SystemRoot%\system32\mswsock.dll 
MSAFD Tcpip [RAW/IPv6] : 2 : 3 :  
RSVP TCPv6 Service Provider : 2 : 1 : %SystemRoot%\system32\mswsock.dll 
RSVP TCP Service Provider : 2 : 1 :  
RSVP UDPv6 Service Provider : 2 : 2 : %SystemRoot%\system32\mswsock.dll 
RSVP UDP Service Provider : 2 : 2 :  
MSAFD RfComm [Bluetooth] : 2 : 1 : %SystemRoot%\system32\mswsock.dll

useragent_locale: en-US

This report also contains technical information about the state of the application when it crashed.

Attempt 2: AdapterDeviceID: 0x0166 AdapterDriverVersion: 9.18.10.3165 AdapterSubsysID: 00000000 AdapterVendorID: 0x8086 AvailablePageFile: 8182980608 AvailablePhysicalMemory: 2379935744 AvailableVirtualMemory: 3909971968 BIOS_Manufacturer: American Megatrends Inc. BlockedDllList: BreakpadReserveAddress: 44302336 BreakpadReserveSize: 67108864 BuildID: 20150525141253 CrashTime: 1434987743 EMCheckCompatibility: true Email: Nfactor26@gmail.com EventLoopNestingLevel: 1 FramePoisonBase: 00000000f0de0000 FramePoisonSize: 65536 InstallTime: 1434878680 Notes: AdapterVendorID: 0x8086, AdapterDeviceID: 0x0166, AdapterSubsysID: 00000000, AdapterDriverVersion: 9.18.10.3165 Has dual GPUs. GPU #2: AdapterVendorID2: 0x10de, AdapterDeviceID2: 0x0fd1, AdapterSubsysID2: 00000000, AdapterDriverVersion2: 9.18.13.5012 ProductID: {ec8030f7-c20a-464f-9b0e-13a3a9e97384} ProductName: Firefox ReleaseChannel: release SecondsSinceLastCrash: 92 StartupTime: 1434987728 SystemMemoryUsePercentage: 62 Theme: classic/1.0 Throttleable: 1 TotalPageFile: 12667805696 TotalPhysicalMemory: 6334840832 TotalVirtualMemory: 4294836224 URL: http://www.bing.com/ Vendor: Mozilla Version: 38.0.5 Winsock_LSP: MSAFD Tcpip [TCP/IP] : 2 : 1 :

MSAFD Tcpip [UDP/IP] : 2 : 2 : %SystemRoot%\system32\mswsock.dll 
MSAFD Tcpip [RAW/IP] : 2 : 3 :  
MSAFD Tcpip [TCP/IPv6] : 2 : 1 : %SystemRoot%\system32\mswsock.dll 
MSAFD Tcpip [UDP/IPv6] : 2 : 2 :  
MSAFD Tcpip [RAW/IPv6] : 2 : 3 : %SystemRoot%\system32\mswsock.dll 
RSVP TCPv6 Service Provider : 2 : 1 :  
RSVP TCP Service Provider : 2 : 1 : %SystemRoot%\system32\mswsock.dll 
RSVP UDPv6 Service Provider : 2 : 2 :  
RSVP UDP Service Provider : 2 : 2 : %SystemRoot%\system32\mswsock.dll 
MSAFD RfComm [Bluetooth] : 2 : 1 : 

useragent_locale: en-US

This report also contains technical information about the state of the application when it crashed.

I tried on 2-3 systems including desktop and laptop. I was able to replicate the issue on all of them.

The crash report is several pages of data that we need to see.

FredMcD said

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there? While still in Safe Mode, In the address bar, type about:crashes<enter>. Note: If any reports do not have BP in front of the numbers/letters, click it and select Submit. Using your mouse, mark the most resent 7 - 10 crash reports, and copy them. Now go to the reply box below and paste them in.

I'm not familiar with this idea of docking Firefox in another application.

Launching a new tab would seem to be a largely "internal" operation, but Firefox does have an optional feature to interact with Windows when doing that. Could you check this option, which defaults to OFF:

"3-bar" menu button (or Tools menu) > Options > General

At the bottom of the Tabs section, if "Show tab previews in the Windows taskbar" is selected, try deselecting it.

@jscher2000 - I tried the suggested setting by turning it on and off . Didn't help.

@FredMcd - Strangely when firefox crashes and i don't submit the crash report , i can't see any entry in about:crash page later. Last time it crashed after docking and trying to open a new tab , i submitted the details using crash dialog that appears. Please refer to url : [|5f4b441d-d7a6-48d4-9956-186c52150623 ] for details. Hope this provides required details you want me to copy paste here.

Hi Nish26, that crash report shows these attempted activities just before the thread crashed:

mozilla::widget::WinTaskbar::CreateTaskbarTabPreview() mozilla::widget::TaskbarTabPreview::TaskbarTabPreview() mozilla::widget::TaskbarPreview::TaskbarPreview() mozilla::widget::WindowHook::AddMonitor() mozilla::widget::WindowHook::LookupOrCreate() mozilla::widget::WindowHook::Lookup() dies on line 67 of WindowHook.cpp

(there are links into the source code from the rows listed under Crashing Thread)

That is consistent with my speculation of how Firefox might be reaching out to Windows when you create a new tab, but since you disabled the feature, I wasn't expecting Firefox to actually try it.

That crash is in a loop relating to a message data array that Firefox may be trying to populate using a Windows API call, but... I don't read C++ (and am not familiar with the APIs even if I did) so I really don't know.

Do you think someone who develops Windows Forms applications would be aware of a solution or workaround based on these tiny fragments of information?

Hi jscher ,

Even i work mostly in .net and have only basic knowledge of C++. Maybe I will try to pull source code during weekends and try to make some sense out of it.

Regards, Nish26