Hi ms.elby, Firefox doesn't come with Yahoo as a search engine choice, so most likely, one of your add-ons brought it in.

You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Command+Shift+a (Windows: Ctrl+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything that mentions "search" or Yahoo, or that you just do not remember installing or why? If in doubt, disable (or remove).

Hopefully after cleaning up extensions, you'll regain control of your search engine choice.

By the way, what happens when you remove Yahoo from the box of search engines. How soon does it come back?

See the "One-click" section of this article: Change your default search settings in Firefox.

For example, it's back before you quit Firefox, after you quit Firefox and restart it, or after you shut down your Mac and restart it.

I already checked the add-ons/extensions. There are none listed. There are two plug-ins, installed by Mozilla and google. Yahoo is not even listed as a possibility in the list of search engines. I removed it. I have now also removed the undefined "default browser." Yahoo comes back within the same session, sometimes. I might go for a couple of hours, minimize the window, come back to it later, and Yahoo is back. It might be poor practice, but I rarely close firefox or restart /shut down my computer. So that definitely isn't a prompt for the bad behavior.

It sounds like a malware infection. Could you try this scanner (free or free trial):

https://www.malwarebytes.com/mac/

You also could try reinstalling Firefox, replacing the program files. I am very familiar with doing that on Windows, but now sure how best to approach it on Mac to get a clean result without losing useful data.

Tried the Malwarebytes and it didn't change anything. Am afraid to uninstall Firefox. Any other suggestions?

Hi sympatica, I assume you already cleaned up your extensions. Since you run Windows 10, could you try this:

Clean Reinstall

This takes about 5 minutes. It's not about your settings, it's about making sure the program files are clean (no inconsistent or alien code files). As described below, this process does not disturb your existing settings. It's not essential to uninstall Firefox, but you can if you like, saying No to any request about removing personal data.

(A) Download a fresh installer for Firefox to a convenient location:

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

(B) Exit out of Firefox (if applicable).

If you use Microsoft Office, please change your default browser to Internet Explorer temporarily before the next step.

(C) Using Windows Explorer/My Computer (hold down the Windows key and press E to launch it), right-click > rename the program folder as follows (you might have one or both):

C:\Program Files (x86)\Mozilla Firefox =to=> C:\Program Files (x86)\OldFirefox

C:\Program Files\Mozilla Firefox =to=> C:\Program Files\OldFirefox

(D) Run the installer you downloaded in step (A). It should automatically connect to your existing settings.

Any improvement at your next startup?

Wanted to say thank you: It just stopped happening. Will keep your advice in case it happens again.

Yahoo is back. So annoying. If I upgrade or wipe the Firefox and reinstall, I'm going to have to go through authentication procedures for every site out there that I do business with. Why can't my preference settings just hold from one session to another? Why do I have to keep going in and changing my preferences back. Yahoo isn't even listed. It's the default search that it sneaks in as. You'd think Mozilla would care about this. Ugh.

My sympathies. Mine just stopped doing that -- don't know how or why.

sympatica

** Updated to Reflect Improvements in Firefox's Profile Manager **

Hi ms.elby, could you try this test:

New Profile Test

This takes about 3 minutes, plus the time to test searching and restart a few times

Inside Firefox, type or paste about:profiles in the address bar and press Enter/Return to load it.

Click the Create a New Profile button, then click Next. Assign a name like March2019, ignore the option to relocate the profile folder, and click the Finish button.

After creating the profile, scroll down to it and click the Set as default profile button below that profile, then scroll back up and click the Restart normally button. (There are some other buttons, but please ignore them.)

After creating the profile, scroll down to it and click the Launch profile in new browser button.

Firefox should exit and then start up using the new profile, which will just look brand new. Firefox should open a new window that looks like a brand new, uncustomized installation. (Your existing Firefox window(s) should not be affected.) Please ignore any tabs enticing you to connect to a Sync account or to activate extensions found on your system so we can get a clean test.

Does your search engine preference "stick" in the new profile?

How about after a few quit/restart cycles?

When you are done with the experiment, open the about:profiles page again, click the Set as default profile button for your normal profile, then click the Restart normally button to get back to it.

When you are done with the experiment, you can close the extra window without affecting your regular Firefox profile.

Well thanks but no thanks jscher2000 ! Halfway through acting on your advice I created the new profile and up came a virgin FF screen with all my working tools deleted and also unable to read the rest of your "advice" which had vanished. I have had to cunningly retrace my steps repeating this morning's tracks that led to this particular Support page to find your advice once more and to read to its end! Please place a warning on top of said advice that halfway view our online life will grind to a standstill.

Meanwhile my hair-rending haunting by the unwanted Yahoo continues unabated since nothing on this page has resolved the problem.

As a fulltime desktop Mac user I am sick to the back teeth of Firefox's stop-start updates that wreck some other aspect of my browser: two more in the past fortnight. I've been driven to use an alternative browser for expediency yet all my business contacts etc live on the FF browser. I first posted in March about Yahoo reasserting itself and nobody who uses a computer for their business has time to keep working though all the possible solutions you propose though I have done over the long weeks since. Yahoo appears nowhere in the browser prefs yet assumes default role in the search bar along the page top.

In another string somewhere on the Yahoo topic you asked how the URL appeared following a Yahoo search. Here's one: https://uk.search.yahoo.com/yhs/search?hspart=Lkry&hsimp=yhs-SF01&ts=sy&type=ANYS_A0XKK_set_bfr&obt9bpdyed=0&p=BREXIT++DATE&param1=na3P9yVrJGqvPvDxtOK2ptDXE4k7h2hUcMJghzydnbBF6YadChJhZQ1UN2F74L1Ak9ji-UOoziioUjwsfV1IQ2p7lQg23SEtksJic97bVCcFgh18E-cNWc49FetcpcLmOqAUlRXmPF_9-1tVNDpwi9LW4b8YAVEm5EsulYMzpGtPQYfhvYWzfRvlOod7NwR5JkGTMoBgQJJw2jNnCeKe-LSaVlZl

• A major update about a fortnight ago stripped FF back to a basic blackbordered page and most annoying of all suddenly offered an extensions page inviting me to download the four extns that had been knocked out, yet the hotlink reported: "Download failed. Please check your connection"! It's years since I customised my browser and can't even remember where to find most of the fixes/shortcuts/blockers I routinely use.

• My Homepage with a menu for four Fastmail email accounts still doesn't offer a consistent dropdown menu ready to click. After a close-and-reopen reload maybe but otherwise involves writing in the account names by hand. There's no consistency and it's maddening.

J1709 said

Well thanks but no thanks jscher2000 ! Halfway through acting on your advice I created the new profile and up came a virgin FF screen with all my working tools deleted and also unable to read the rest of your "advice" which had vanished. I have had to cunningly retrace my steps repeating this morning's tracks that led to this particular Support page to find your advice once more and to read to its end! Please place a warning on top of said advice that halfway view our online life will grind to a standstill.

I recently started using a different approach to the New Profile test, but this was an older post. I'll update it.

J1709 said

Yahoo appears nowhere in the browser prefs yet assumes default role in the search bar along the page top.

On the Preferences page, Search panel, what is your default search engine set to?

Ref. Change your default search settings in Firefox

In another string somewhere on the Yahoo topic you asked how the URL appeared following a Yahoo search. ...hsimp=yhs-SF01...

Thanks for the link. Although I don't know that affiliate code, the results page is co-branded "safe finder" in the upper right corner --

-- so you may have an add-on or infection named or related to "safe finder" that is setting your default search engine.

A major update about a fortnight ago stripped FF back to a basic blackbordered page and most annoying of all suddenly offered an extensions page inviting me to download the four extns that had been knocked out, yet the hotlink reported: "Download failed. Please check your connection"!

Around the weekend of May 4th? That should have been fixed within the following several days, unless you run an old version. Please see: Add-ons disabled or fail to install on Firefox.

My Homepage with a menu for four Fastmail email accounts still doesn't offer a consistent dropdown menu ready to click. After a close-and-reopen reload maybe but otherwise involves writing in the account names by hand. There's no consistency and it's maddening.

Your other thread (https://support.mozilla.org/questions/1254062) is still open for that issue, let's keep this one on the Yahoo problem, and you can update/reply on the Fastmail issue over there.

Every time I get Yahoo as a result of a search, I go to my settings, go to "search," and find that the "default" is back, and checked. As always, I delete the "default" and then I can have my google back. Invariably, though --if I close firefox, if I restart my computer, if firefox crashes (and it does often)-- the "default" comes back, and comes back as Yahoo. I keep getting told that Yahoo is not a default search engine, and yet... there it is, over and over again. No extensions. No add-ons.

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

Hi ms.elby, this thread is a little confusing because different people have come through and hijacked the discussion.

Q1: Can you share the URL of the results page? Sometimes Yahoo "affiliate" pages have special branding indicating what company is responsible.

Q2: Did you try a malware cleaning: https://www.malwarebytes.com/mac/

Thanks for the analysis and I see "SAFE FINDER" top right of the browser but you don't suggest how to delete it. I've searched my Mac for these words and there's no sign of it.

J1709 said

Thanks for the analysis and I see "SAFE FINDER" top right of the browser but you don't suggest how to delete it. I've searched my Mac for these words and there's no sign of it.

Hi J1709, please start with my initial suggestion at the top of this thread: carefully check your add-ons. https://support.mozilla.org/questions/1252462#answer-1203282

If the diversion is not caused by an add-on, then we would move on to possible configuration files injected in the Firefox app path or malware on your system.

Hi again - I checked add-ons way back, and have difficulty understanding much of the other advice. Malwarebytes won't download because my Mac OS is too old. I created a new profile but that didn't seem to lead anywhere.

J1709 said

I created a new profile but that didn't seem to lead anywhere.

I'm not sure what do you mean. If you start Firefox in a new profile, what happens when you try to do a search?