I just found a puzzling bit in the Firefox browser. If I open the Options, at the top of the “General” page I see this:
“Your browser is being managed by your organization”
It’s a clickable link that takes me to another page, “Enterprise Policies” which shows:
Sorry if that looks a bit confusing in the OP - some key combo I pressed somehow auto-clicked the “Post Reply” button before I was finished typing, and I had to click “Edit” and try to finish before the timer expired.
Home computer. My Avast AV software installed a couple plugins, though the only one I left active is the “Avast Passwords” to store my, well, passwords. Aside from that, I’m using:
Ghostery (ad/tracking blocker)
HTTPS Everywhere (forces HTTPS connections for sites that don’t offer it)
uBlock Origin (Hmm, maybe I don’t need two ad blockers)
DuckDuckGo Privacy Essentials
That’s a rather iffy thing that Avast does, apparently, even though you uninstalled the extension. What it does is tell Firefox to use the Windows certificates, where it probably installs its own certificate.
I wouldn’t feel comfortable with that enabled. Other software might try to install certificates there.
Fortunately, it’s not hard to fix. It’s just a single file. Find your Firefox install directory (probably either C:\Program Files\Mozilla Firefox or C:\Program Files (x86)\Mozilla Firefox), and open the Distribution folder. Find the file policies.json and either delete it, or if you’re concerned, try renaming it to something like policies.json.bak.
Do this with Firefox closed, BTW. After that, launch Firefox and see if it fixed it.
(One way to find Firefox’s install directory is to right click on the Firefox icon on the desktop, then choose "Open File Location.)