Hi Phil, I don't know why the May "hotfix" -- which installed a new certificate into Firefox's certificate store -- would have any ongoing effects. However, if you already already, you can remove that hotfix since it is not needed in Firefox 66.0.4 or later.

Are you saying that at some point Firefox becomes unable to load pages until you restart Windows, or that all Windows apps lose internet connectivity? Of course, neither is normal...

Does this seem to occur around the same time of day? Does it make any difference if you exit out of Firefox before that time?

I'm remembering more now. - This "hotfix" or whatever was a workaround for Add-ons (e.g. adBlock Plus) that were shown as un-certified (don't know if that's the right word) and therefore disabled by a Mozilla update (or some such).

The fix was to allow "studies" (a way to run ?beta? updates, rather than waiting for official update ?? that's my interpretation ??). The notes I cut & pasted into Notepad at the time are, in full :

<< FireFox Add-Ons disabled 3 May 2019 - It may take up to six hours for the study to be applied to Firefox. To check if the fix has been applied, you can enter about:studies in the address bar. If the fix is active, you’ll see hotfix-reset-xpi-verification-timestamp-1548973 You may also see hotfix-update-xpi-signing-intermediate-bug-1548973 listed, which is part of the fix and may be in the Active or Completed section. >>

That should be verbatim apart from the 1st line heading I put in.

I didn't think to try IE or Edge, the fact that FFox being re-started used to help, made me assume it was FFox to blame, and the timing i.e. soon after the "fix". My phone had normal wi-fi response.

It can happen at any time, tho' it usually takes hours of use in any day, I think, rather than 1st thing in a.m. (I never shut down my laptop/tablet; just close the lid for the night, and Ffox & other apps are minimised).

I always have the NetWorx real-time usage graph open and at these time it just shows usual background activity, i.e. a few kbit/sec to and fro, rather than the usual blue bar and several Mbit/sec incoming.

Thanks for your response, sorry about length of reply - it's difficult without a greater knowledge of computer workings and terminology. cheers, Phil.

Hu Phil157,

It might be a Windows problem. Take a look at this:

https://answers.microsoft.com/en-us/windows/forum/all/windows-10-pro-loss-of-internet-after-sleep/c5ad2752-cd6e-4d38-a396-ed4f325ec2ed

Thanks MyCIS - There's a lot of suggestions there and as my problem isn't every time after sleep I've just tried the 1st for now. i.e. Unchecked the "switch wifi off to save power" option. I'll see how it goes. Having asked the question the problem hasn't occurred since. Typical! Phil.

You can create a new profile to test if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

• https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

Thanks for all the replies.

Now, when I opened my laptop early evening yesterday Ffox connection was stalled. Instead of re-starting I opened IE and Edge. From BBC news headline links - The new tab in FFox was blank with the timer icon on the tab of the tab spinning. IE opened ok and Boris was soon blabbing about new PMs. Edge was likewise. Similarly Teresa May was OK in IE and Edge, Ffox was unchanged & didn't change with closing & opening a tab. IE continued. but failed with Trump. So, the winner is... MS Edge.!

Oh, and OneDrive happily uploaded several files.

Ffox remained blank and when I tried to close & re-open it I got msg. that Ffox was already open and I couldn't get past that. Opened Task Manager and found multi-occurences of Ffox in Background Processes - End Task did shut some, but never all, and new occurences kept popping up (showing 5 or 6 max).

Does this help anyone with a diagnosis?

P.S. cor-el - I know zero about Profiles, but how do you avoid copying corrupt files??

Phil. (where is it 6:42 AM? Must be Pacific Daylight Time? I'm in UK)

Good Morning Phil,

Yes. 6:42 was PDT. I'm on MDT so, I'm an hour closer to you, I think. But then, I'm still working on my first cup of coffee.

Not long ago, I had a "rogue" process in Firefox. I'm certain that it was left over from an extension which included a 'remote injection' file - a bad guy. That extension has been blocked from availability. I consistently have 5 processes running for Firefox.

In other words, I'm saying that there is the possibility that you have a 'bug' in Firefox. You should run a scan with anti- virus or anti-malware.

Have you tried starting Firefox in Safe Mode? The easy way is to press and hold the shift key while you launch Firefox. A dialog window will appear asking to start in Safe Mode. Do not select Refresh.

Try that and see what happens.

Hi My_CIS, I've had a quiet w/end. I re-ran scans by BitDefender and Spybot - Search & Destroy with only trivial warnings, as usual. I also tried Safe Mode as you suggested.

I think because of less use, I only had a FFox interruption on Tuesday evening, so no change.

I've remembered, though, that I have a tab freeze (no response, unable to click into another tab) every now & again; and I can get things going again by right-clicking the taskbar icon and selecting "Close window"; followed by cancelling the FFox pop-up for closing multi-tabs. Don't know if this is a "useful" symptom??

Hi Phil, I'm glad to hear that you had a restful weekend.

So, we probably ruled out any kind of malware in Firefox. That's a good thing.

A tab freezing could be the result of internet connection loss, which is pointing me back to the Windows update issue. It is an intermittent problem which are the worst to troubleshoot.

At this point I can only suggest that you continue attempting to resolve the Windows problem or simply wait for a Windows update which resolves it for you.

Yeah, intermittent is difficult - thanks for your input, let's relax and see how it goes. I may return to try some of the other suggestions at a later date. cheers, Phil  :o)