Hi, please run a scan using this : https://www.malwarebytes.com/

After please give this a try : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 61.0.2 with a Full Version Installer

• https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

Note that your Extensions could be the issue : Token signing Firefox PKCS11 loader as there was a bug for this a few versions ago, 58

SAFE MODE

• https://support.mozilla.org/kb/Safe+Mode
• https://support.mozilla.org/kb/Troubleshooting+extensions+and+themes

In Firefox Safe mode these changes are effective:

• all extensions are disabled (about:addons)
• default theme is used (no persona)
• userChrome.css and userContent.css are ignored (chrome folder)
• default toolbar layout is used (file: localstore-safe.rdf)
• Javascript JIT compilers are disabled (prefs: javascript.options.*jit)
• hardware acceleration is disabled (Options > Performance > Uncheck to view)
• plugins are not affected
• preferences are not affected

TEST''''is issue still there ?

Pkshadow said

Hi, please run a scan using this : https://www.malwarebytes.com/ After please give this a try : uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

• https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles
• https://support.mozilla.org/en-US/kb/export-firefox-bookmarks-to-backup-or-transfer

Reinstall with Current Release Firefox 61.0.2 with a Full Version Installer

• https://www.mozilla.org/firefox/all/

Please let us know if this solved your issue or if need further assistance.

Thanks, this is basic, but hopefully works. If I do not come back, it worked.

Thanks, Kaido

Khmm. The issue still persists, although less frequently.

First, after doing everything in post 8/27/18, 6:05 PM and having a week of non-hang on a new (ie. 3-4 weeks old) profile, I opened FF with old profile. FF hanged very soon. I then killed FF and used the new profile, which also started hanging... as if something from the old profile took over FF. Malwarebytes installed and clean.

So I re-did everything as instructed in post 8/27/18, 6:05 PM and used only the new profile. For most part FF runs fine, but sometimes (once a week, now twice per 2 days) still hangs random times and on random pages.

I do use Token signing and Firefox PKCS11 loader. I have always used them in FF. And when on old profile, disabling these did not help. I disable these now on newer profile, and see.

Is there a way to see what chokes FF? Why/where it hangs? I only see a non-responsive page and it is not sufficient for real trouble-shooting.

Thanks, Kaido

Random hang still continues even with Token signing and Firefox PKCS11 loader disabled.

I still experience a completely odd thing: FF becomes non-responsive, I start IE, and IE does not open until I have killed FF (no messages until FF is killed, then IE shows up). What is this? What in the world prevents IE from opening? Is it a win10 "network stock" that "goes broke"?

It appears as if installing any extension makes FF to hang randomly.

Any ideas?

Is there a way to see what chokes FF? Why/where it hangs? I only see a non-responsive page and it is not sufficient for real trouble-shooting.

Somestimes I do use VPN, but this hang happens also during non-use.

Any ideas? I am crying here...

I tried restricting FF to single process (instance) with browser.tabs.remote.autostart FALSE but this did not help.

This seems to be accompanied with general slowness of FF. Other browsers (IE) work as intended.

All updates are installed.

Please help.

In Safe mode, FF is lightning-fast, much faster than in normal mode. It is like something is sitting on the datastream in normal mode...

Help, please.

Kaido

In Win10 safe mode and FF normal mode, FF is fast. So it seems to be something outside of FF.

Renaming cert9.db does not help.

How to make sure my win10 network settings are good?

Any ideas?

Disabling all win10 startup items did not help. Disabling all win10 services did not help. Resetting win10 networking settings did not help.

Out of ideas here...

Kaido

Excluding firefox.exe from MS Defender does not help.

Help please.

Excluding firefox.exe from MS Defender exploit protection does not help.

Go into windows control panel, device manager, click on tab at top, ‘show hidden devices’, look for your network adapters, and delete everyone single one you find, BUT KEEP DRIVERS WHEN ASKED’.

I know that sounds extreme, but Windows has a habit of creating many extra virtual adapters, especially if you’ve ever used the ‘fix my connection’ function windows has.

Because you’ve kept the drivers, when you reboot, windows will find your network adapters, and reinstall them, this will give you a clean slate with windows networking.

If it runs fine in safe mode, then it really is a windows issue, you didn’t say if you were connecting via Ethernet cable or wireless, but I’ve had quite a few clients with WiFi issues after the October Windows 10 update, and in those cases I’ve used an earlier WiFi driver on their system to cure it.

Ethernet is fine though. Let me know if this helps, Fred

It is official, the culprit must be something related to eID smart card signing software (token signing or smth). When its AddOns are deinstalled, FF starts working normally (disabling does not have this effect). Have made a complaint to AddOn manufacturer, no response in 7 days or more.