This posting is somewhat off topic for me, but then it is on topic, because the issues I am discussing initially appeared to be in Mozilla branded products. I am a glutton for punishment sometimes, and as a result I run daily builds of both Firefox and Thunderbird. The result of this is a mostly reasonable experience with occasional disaster days where you get a Thunderbird or Firefox that basically does not load at all.
In July I bit the bullet and updated Windows to version 10, the motivation was more a case of I had seen many people in the support forums with Windows 10 issues and really they appeared to be largely inexplicable than any desire to use the latest and greatest from Microsoft.
In all the upgrade of my Dell Vostro went well. I read the options closely enough to find the tiny option to keep my existing settings and after a number of hours I was away with the new Windows 10. I turned off all the phone home things Windows 10 wanted to do, I stopped Cortana and got rid of all the rubbish in the start menu. Things were looking positive.
So here I am in August, frustrated by Mozilla Firefox. It is horrible and getting worse. It just stops responding for anything from a few seconds to a minute or more. Typing in reply dialogs on support.mozilla.org just stops mid word. When it returns large chunks of what was typed is simply not there, not in some buffer waiting for the freeze to end, just not there.
Then Thunderbird started to display this same abhorrent behaviour. It just stops responding. Sometime it says it is not responding, other times it just does nothing. At least it is not as bad as Firefox. But it appears to be getting worse
Then I noticed something new. The command window in Windows 10 was also freezing. This was when I realized I had an issue with Windows, or some other software freezing windows, not Mozilla branded software at all.
I started searching on the web and it really only took a few moments to see I was not alone. There were lots of folk apparently experiencing hangs or freezing. In my usual approach to these things I read a few of the first hits I got from Google, looking for similarities and common solutions. Then I clicked on a link to a YouTube video that offered to fix windows 10 freezing. Cynic that I am I though what are they selling. Well nothing is the answer! Except a free solution for me.
I found that of the settings mentioned in the video, only the PCI express setting appeared in power on my desktop. So like the guy in the video I tuned the setting in power management off. That was a couple of days ago now. I have experienced no freezing at all since that change.
The lesson for me was just how much of my computer time is spent in Firefox and Thunderbird. I had the problem for weeks and never even considered I was looking in the wrong place for a solution.