Firefox 21.0 crashes I attempt to open a page containing video

Question

When ever I open any page containing a video, such as any youtube page my browser immediately closes and presents me with a crash report I believe this started happening after a firefox or adobe update a few weeks ago. The problem continues when Im in safe mode and Ive tried many suggested fixes including updating flash, reinstalling firefox, disabling hardware acceleration, checking for conflicting realplayer, editing my the flash cfg file, and so on but non of those had any effect and It's sad cause I know from looking though these forums and elsewhere that others are having the exact same problem and these solution aren't working for anyone.
I couldn't find any answers to the problem so I reverted to firefox 20.1 decided to wait for next update, as there seems to be a flash update a couple weeks. Somehow I ended up back on FF21.0 and so Im here again asking the same question before I re-revert. So here are the details again.
Im Post my reports and spec like this because non of these options; "automatically" "try these manual steps" or "Show details" work for me in my outdated IE which is the only working browser I have atm. The first report shows results with addons enabled and all my usual settings the second show results with in safe mode. As you can see the two are the same for the most part
The report: With addons enabled
AdapterDeviceID: 0x6719
AdapterVendorID: 0x1002
Add-ons: yesscript%40userstyles.org:1.9,optout%40google.com:1.5,foxyproxy%40eric.h.jung:4.2,adblockpopups%40jessehakanen.net:0.7,%7B73a6fe31-595d-460b-a920-fcc0f8843232%7D:2.6.6.2,%7B972ce4c6-7e08-4474-a285-3208198ce6fd%7D:21.0
AvailablePageFile: 4682809344
AvailablePhysicalMemory: 1420525568
AvailableVirtualMemory: 3792789504
BuildID: 20130511120803
CrashTime: 1370577662
EMCheckCompatibility: true
Email:
FramePoisonBase: 00000000f0de0000
FramePoisonSize: 65536
InstallTime: 1369263628
Notes: AdapterVendorID: 0x1002, AdapterDeviceID: 0x6719, AdapterSubsysID: 24611462, AdapterDriverVersion: 9.12.0.0
D2D? D2D+ DWrite? DWrite+ D3D10 Layers? D3D10 Layers+
ProductID: {ec8030f7-c20a-464f-9b0e-13a3a9e97384}
ProductName: Firefox
ReleaseChannel: release
SecondsSinceLastCrash: 1109
StartupTime: 1370577654
SystemMemoryUsePercentage: 62
Theme: classic/1.0
Throttleable: 1
TotalVirtualMemory: 4294836224
URL: https://plus.google.com/u/0/_/notifications/frame?origin=http%3A%2F%2Fwww.youtube.com&source=yt&hl=en-US&jsh=m%3B%2F_%2Fscs%2Fabc-static%2F_%2Fjs%2Fk%3Dgapi.gapi.en.YwZcwvhQD7M.O%2Fm%3D__features__%2Fam%3DIA%2Frt%3Dj%2Fd%3D1%2Frs%3DAItRSTNqkRhMtkpSA0AbmH0iColYw_JJwg#pid=36&rpctoken=387582488&_methods=setNotificationWidgetSize%2CsetNotificationWidgetHeight%2CsetNotificationText%2ChideNotificationWidget%2CopenSharebox%2ConError%2C_ready%2C_close%2C_open%2C_resizeMe%2C_renderstart&id=I1_1370577662087&parent=http%3A%2F%2Fwww.youtube.com
Vendor: Mozilla
Version: 21.0
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 :
This report also contains technical information about the state of the application when it crashed.
(Im Post my reports and spec like this because non of these options; "automatically" "try these manual steps" or "Show details" work for me in my outdated IE which is the only working browser I have atm)
AdapterDeviceID: 0x6719
AdapterVendorID: 0x1002
AvailablePageFile: 4607332352
AvailablePhysicalMemory: 1334870016
AvailableVirtualMemory: 3936632832
BuildID: 20130511120803
CrashTime: 1370580940
EMCheckCompatibility: true
Email: [email protected]
FramePoisonBase: 00000000f0de0000
FramePoisonSize: 65536
InstallTime: 1369263628
Notes: AdapterVendorID: 0x1002, AdapterDeviceID: 0x6719, AdapterSubsysID: 24611462, AdapterDriverVersion: 9.12.0.0
ProductID: {ec8030f7-c20a-464f-9b0e-13a3a9e97384}
ProductName: Firefox
ReleaseChannel: release
SecondsSinceLastCrash: 290
StartupTime: 1370580845
SystemMemoryUsePercentage: 64
Theme: classic/1.0
Throttleable: 1
TotalVirtualMemory: 4294836224
URL: https://www.youtube.com/watch?v=saKv2djbQ5s
Vendor: Mozilla
Version: 21.0
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 :
This report also contains technical information about the state of the application when it crashed.
My specs:
Firefox ver. 21.0
Flashplayer 11.7.700.202
OS Windows 7 Professional (x64)
Version 6.1.7601 Service Pack 1 Build 7601
Mobo BIOSTAR Group / TZ77XE3
System Type x64-based PC
Processor Intel(R) Core(TM) i5-3570K CPU @ 3.40GHz, 3401 Mhz, 4 Core(s), 4 Logical Processor(s)
BIOS Version/Date American Megatrends Inc. 4.6.5, 4/19/2012
SMBIOS Version 2.7
Windows Directory C:\Windows
System Directory C:\Windows\system32
Boot Device \Device\HarddiskVolume1
Hardware Abstraction Layer Version = "6.1.7601.17514"
Installed Physical Memory (RAM) 8.00 GB
Total Physical Memory 3.48 GB
Available Physical Memory 1.41 GB
Total Virtual Memory 6.96 GB
Available Virtual Memory 4.46 GB
Page File Space 3.48 GB

Answer 1

You probably have not seen anyone reporting the exact same problem as you. All three crash reports have the same crash signature and as currently ranked 67 it is not the commonest of reasons for a crash.
I hope you enter your email contact information when reporting crashes. I note you see this crash when using videos, others may possibly see this crash in other circumstances.
You have already tried the obvious, attempts at a fix so it is now down to wait and see, maybe developers working on the bug will report something or fix it.
Did you try my suggestion of installing portable ESR ?
For forum cross referencing purposes
* Crash Reports for Crash IDs <br />bp-71697f5d-41d4-48ae-9db9-3e6302130607<br /> bp-6e1347bc-153f-433a-9c35-a5f022130607<br /> bp-92a533a2-9e09-4c1e-8df7-deb4c2130607
*(all three) Crash Signature: EnumSoftwareMFTs(_GUID const&, unsigned int, __MIDL___MIDL_itf_mfobjects_0000_0006_0003 const*, __MIDL___MIDL_itf_mfobjects_0000_0006_0003 const*, IMFActivate***, unsigned int*)
* Related bug 858667 NEW crash in mozilla::wmf::MFTEnumEx @ EnumSoftwareMFTs
*I note this was first seen in Fx21 and is 100% Windows 7
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