Additional Information:

1. Windows Memory Test showed no error. RAM is healthy. 2. All other apps and programs run without any problems. 3. RAM frequency decreased from DDR4 3600 to 2133.

Still multiple firefox tab crashes. Firefox also did hang couple of times recently.

more crashes: bp-ff4c4044-ab9f-4cc3-b739-e15690210607 bp-ea83ac2e-da7a-41be-812c-ce45a0210607 same reason.

still more crashes:

bp-b05b0b1b-8f2e-47e7-bb7d-a38120210607 bp-87a29c0d-282d-4971-949c-fdb190210607 bp-33cb981f-5741-472c-a338-9ea5a0210607

1st one crashed firefox completely.

bp-b05b0b1b-8f2e-47e7-bb7d-a38120210607 Signature: JS_InitializePropertiesFromCompatibleNativeObject

Crash Reason EXCEPTION_ACCESS_VIOLATION_READ

This is for Sumo's Related Bugs 1488077 RESOLVED DUPLICATE Crash in JS_InitializePropertiesFromCompatibleNativeObject ++++++++++++++++++++++++++++++++++++++++++++++++ bp-87a29c0d-282d-4971-949c-fdb190210607 Signature: js::TenuringTracer::onObjectEdge

Crash Reason EXCEPTION_ACCESS_VIOLATION_READ

This is for Sumo's Related Bugs 1582214 NEW --- Crash in [@ js::TenuringTracer::traverse<T>] +++++++++++++++++++++++++++++++++++++++++++++ bp-33cb981f-5741-472c-a338-9ea5a0210607 Signature: mozilla::StyleGenericCalcNode<T>::~StyleGenericCalcNode

Crash Reason EXCEPTION_ACCESS_VIOLATION_READ

Did you see any error messages when launching Firefox, such as "VCRUNTIME140_1.DLL is not found"?

You can check for issues caused by a corrupted or incomplete Visual C++ installation that is missing runtime components (Redistributable Packages) required by Firefox, especially VCRUNTIME140_1.dll.

In that case, I would install both 32-bit and 64-bit "Visual Studio 2015, 2017 and 2019" downloads, (x86: vc_redist.x86.exe and x64: vc_redist.x64.exe) from https://support.microsoft.com/help/2977003/the-latest-supported-visual-c-downloads

I did not see "VCRUNTIME140_1.DLL is not found" message

firefox always started normal, without any problems, then later tabs start crashing and application itself may crash completely.

from Windows Log it looks like the 1st crash event was with Version 88.0: Faulting application name: firefox.exe, version: 88.0.1.7794, time stamp: 0x60917823 Faulting module name: xul.dll, version: 88.0.1.7794, time stamp: 0x6091784a Exception code: 0xc0000005 Fault offset: 0x000000000054f2c5 Faulting process id: 0x1fc0 Faulting application start time: 0x01d7549475632118 Faulting application path: C:\Program Files\Mozilla Firefox\firefox.exe Faulting module path: C:\Program Files\Mozilla Firefox\xul.dll Report Id: 154bea71-f77e-4693-96f3-d7adeab3b561

I did not see "VCRUNTIME140_1.DLL is not found" message

Please run the install programs anyway. We have been seeing problems with vcruntime of late. https://support.mozilla.org/en-US/questions/1339469#answer-1419160

I did install both 32-bit and 64-bit "Visual Studio 2015, 2017 and 2019" Visual C++ redistributable packages, (x86: vc_redist.x86.exe and x64: vc_redist.x64.exe) from the link above. I will post results.

It did crash the tab today again:

bp-7f599557-7cbe-4762-a999-aa3220210608 bp-574e0cc6-61be-4dac-a644-644f60210608

bp-7f599557-7cbe-4762-a999-aa3220210608 Signature: js::jit::CodeGeneratorShared::generateOutOfLineCode

Uptime 80 seconds (1 minute and 20 seconds)

MOZ_CRASH Reason (Sanitized) : MOZ_RELEASE_ASSERT(src.offset() > int32_t(sizeof(int32_t)))

Crash Reason EXCEPTION_BREAKPOINT +++++++++++++++++++++++++++++++++++++++++++ bp-574e0cc6-61be-4dac-a644-644f60210608 Signature: cairo_surface_get_extents

Uptime 67 seconds (1 minute and 7 seconds)

Crash Reason EXCEPTION_ACCESS_VIOLATION_READ

Diagnose Firefox issues using Troubleshoot(Safe) Mode {web link}

A small dialog should appear. Click Start In Troubleshoot(Safe) Mode (not Refresh). Is the problem still there?

Start your Computer in safe mode with network support. Then start Firefox. Try Secure websites. Is the problem still there?

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode Starting Any Computer In Safe Mode; Free Online Encyclopedia

If the problem goes away with the computer in Safe Mode, the problem is with one of the other programs on the system.

As a test, disable your protection programs.

and another two crashes: bp-95d43b9c-d33c-454d-b381-dd79f0210608 bp-a7e358b8-dc39-42e2-96ca-c02360210608

It also crashes in the troubleshooting mode: bp-c68cbefd-0dbd-45da-8930-3e03a0210608 bp-f0ed4a57-3566-422c-a83e-cb3ef0210608 bp-129b8124-36c3-491d-a8ad-43d0a0210608 bp-44b9204c-96c8-4782-b7ea-be2410210608 also did crash on Firefox Troubleshooting page as well. security software, except windows firewall, is off currently. It also crashed with firewall disabled.

Use these links to create a new profile. Use this new profile as is. Is the problem still there?

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

http://kb.mozillazine.org/Profile_folder_-_Firefox#Navigating_to_the_profile_folder

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Type about:profiles<enter> in the address bar.

well, I did full refresh with 2nd re-install of Firefox 89.0 and this means a new profile, but problem persisted.

I will test it with different RAM modules, when I'll have them. I have no problems on two other computers - PC and a laptop - the differences are: installed KB5003214 and ASUS MB software (on this one). In case of a conflict with ASUS software (which uses C++ Redistributable as well) I will be forced to use another browser. As noted previously, before version 88.0 there wasn't a problem. Maybe an update to 90/91 or next Win10 update will bring some changes, who knows.

I called for more help.

more recent crashes: bp-9772a631-8997-4751-94f9-ed1180210612 bp-087ad6c5-effa-4fc2-8c9a-dc6170210612 bp-10d09b99-2388-43ee-9680-3fc840210612 bp-c8c43333-fcb7-44f9-a44c-3a33e0210612 bp-47b256b8-d002-461e-873c-070100210612 bp-11ab585e-4c06-4c59-807e-f21550210612 bp-26ea3652-c026-4bb6-9ad0-6100f0210612

bp-a33def10-6640-4bb6-a71e-823570210611 bp-c0df757a-8923-4752-9a54-aeaf90210611 bp-89e0d6b9-8b15-4809-9346-7ee3a0210611 bp-9471a86e-ad8b-432c-bfe2-a81b30210611 bp-e8d501aa-1c2a-4017-a96c-29c620210611 bp-ffd571cb-2727-4128-898f-f95db0210611 bp-38e9ed6a-f1cd-405a-a372-e37ec0210611 bp-45cab46d-83e8-4365-ad13-0128d0210611 bp-e19f2039-7d75-4c95-b287-9a1910210611 bp-57fe4d05-b10e-4bf6-b1da-11a7c0210611 bp-afe7327b-9e2b-4295-9ef4-218e10210611 bp-afe7327b-9e2b-4295-9ef4-218e10210611 bp-cb8a38a3-b042-44a0-8737-d26e90210611 bp-283bbec9-8518-4a82-a802-7a5ce0210611 bp-4d79c29b-f99f-4216-8e2e-8e06d0210611 bp-91877b83-7d4e-456b-b8ed-61faa0210611 bp-76385a58-1375-4f18-baa8-bc8130210611 bp-597329c2-87d1-437c-88ce-3b1aa0210611

RAM modules exchanged, with different type: was DDR4-3600/C18, installed DDR4-2400/C14. Same problems. All RAM tests run without problems - this is definitely not RAM problem, but something else. Recently some MS Office software crashes, but rare. Firefox does it most of the time, without any system or logic: at start or later, same page may work and may crash later. Did extensive system tests. Intel Processor Diagnostic Tool test fails at prime number test, Prime95 test fails as well. AIDA64 shows unstable FPU - hardware problems with FPU and memory test. FPU fault ? But no BSODs, everything else, including some math simulation software runs as usual. Hyperthreading disabled, CPU (i7-10700) turbo mode off - same problems, used one CPU core instead of 8 - same problems (just slower). It started on May 28th (Firefox 88.0 crashed), all I did that day was some MS Office (MSO2019) software update, not much else. Summary: I do not get it.