Lucy, I'm so sorry, but those pop-ups are from phishing sites trying to trick you into installing malware on your system.

Try using an ad blocker such as the following to suppress the scam ads: https://addons.mozilla.org/firefox/addon/ublock-origin/

But if you accepted any of those files, and your antivirus software didn't block it (you would know -- there's usually a big notification of blocked malware), you'll need to clean your system. See this article for suggested free cleaning tools: Troubleshoot Firefox issues caused by malware.

Regarding performance issues, one of the headline changes in Firefox 48 is that some users have a new feature enabled (e10s), which separates the browser interface process from the page content process. The performance impact of this can vary a lot between systems, so could you check whether you have this feature turned on? Either:

• "3-bar" menu button > "?" button > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, check the row for "Multiprocess Windows" and see whether the number on the left side of the fraction is greater than zero. If so, you are using e10s.

If Firefox is not performing well with e10s enabled, you could try turning it off here:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful.

(2) In the search box above the list, type or paste autos and pause while the list is filtered

(3) Double-click the browser.tabs.remote.autostart.2 preference to switch the value from true to false

Note: the exact name of the preference may vary, but it will start with browser.tabs.remote.autostart

At your next Firefox startup, it should run in the traditional way. Let us know if you notice any difference.

Thank you.

Besides the advise of using an ad blocker, I have a bad feeling that you downloaded an 'update' from the orange screen which was NOT a Firefox source. Many people get the phony 'you need to update' screen and best indication is is a combination of how fancy advertisement tracking has become AND some advertiser who isn't an advertiser at all. That or some network is redirecting people to the wrong machine/place on purpose. this has been happening heavily since Feb., but has been seen since 2013.

What is download seems to be either malware or adware (sounds like your situation) or something worse.

As a contributor who has not worked on the programming of FireFox, I do not offer the following as a sure bet, but, I would totally uninstall FF including any associated files like bookmarks (1. a bummer, 2. I don't know how complete uninstall is) A new install may/should put things right, unless there is leftover stuff (like in Windows registry ... I don't know) which could let the pop-ups reoccur.

I myself restored the registry (system restore) from a date before I had downloaded the phony-update-version of FF in March.

Unfortunately, only so many restore points can be saved and I found that Flash player updates create a restore point.

Do take notice when the last Windows Update actually happened. Some people have found that their CPU runs at 50 percent when idle AND the connection to Microsoft never actually downloads anything (Windows 7.)

I can offer no more.

Thank you for the URL of the "orange screen." It is unusual that that site has stayed up this entire day. My guess is no one reported it to any of the standard virus/malware reporting sites. The main URL you shared only lasts a day. The site you were on before you got that orange screen might help narrow down HOW. However, the companies involved are not helpful in sharing info (registration, network, even web sites selling the advertising space.

In closing, the phony updates are sometimes only mentioned on the sites the people use. Hence, a games site would have a blog and someone reports the pop-up. News sites of course don't have blogs.

Thank you all very much, I restored my windows to the last update setting and followed the directions posted above. The orange firefox page has stopped showing up along with the blaring voice from a Windows 10 screen saying I needed to call a phone number for immediate removal of malware.

I believe it started when I was trying to update a photo editor program from download.cnet.com/windows. I never had a problem before on the site, in fact that was where I first learned about Mozilla Firefox and downloaded the original program for Windows XP and never had a problem.

Oh its back now. This time while checking my email. I think it is ad related. This is the site address for the mozilla orange page:

https://peicigsconto.org/1992926502561/17055d2d020561207526f76f0a489d44.html

Once it opens it tries to automatically download a file. Which luckily my firefox settings blocks downloads without permission now.

I was posting a story from CoasttoCoastAM.com to my facebook page about creepy clowns.

LucyNewman said

Oh its back now. This time while checking my email. I think it is ad related. This is the site address for the mozilla orange page: https://peicigsconto.org/1992926502561/17055d2d020561207526f76f0a489d44.html Once it opens it tries to automatically download a file. Which luckily my firefox settings blocks downloads without permission now.

Thank you for report as I added site to my list and discussion thread about these sites at at https://support.mozilla.org/en-US/forums/contributors/712200

One link blocked. Now this one pops up and is on my block list. New orange mozilla page is https://feecuearncash.net/3782926502561/6f6392accfdab227c686d2b4a65956ac.html

This popped up while visiting Coast to Coast AM.