When did this problem start? Your Firefox identified itself as Firefox 47, whereas the August 2nd update was to Firefox 48.

If you installed a "patch" or .js file update from a web page with a Firefox Logo, you may have been fooled into installing malware. Please run this program first: https://www.malwarebytes.com/mwb-download/ (free version)

Assuming you installed something else that is diverting your searches, please try the following to clean it up. I know it seems long, but it's really not that bad.

(For Windows Vista, 7, 8, 8.1, 10; XP is somewhat different)

(1) Open the Windows Control Panel, Uninstall a Program. After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help in smoking out undisclosed bundle items that snuck in with some software you agreed to install. Be suspicious of everything you do not recognize/remember, as malware often uses important or innocent sounding names to discourage you from removing it. Take out as much trash as possible here.

(2) Open Firefox's Add-ons page using either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons
• in the Windows "Run" dialog, type or paste
  firefox.exe "about:addons"

In the left column, click Plugins. Set nonessential and unrecognized plugins to "Never Activate".

In the left column, click Extensions. Then, if in doubt, disable (or Remove, if possible) unrecognized and unwanted extensions. All extensions are optional; the troublemaker might not be obvious from its name.

Often a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step.

Any improvement?

(3) You can search for remaining issues with the scanning/cleaning tools listed in our support article: Troubleshoot Firefox issues caused by malware. These on-demand scanners are free and take considerable time to run. If they finish quickly and especially if they require payment, you may have a serious infection. I suggest the specialized forums listed in the article in that case.

mArcb49 said

Since last Firefox update, each time I use Google to search, the results are provided by Bing !!!! with bad search results.... and poorly presented...

Yes,   that's Bing alright   .......
You didn't get that   'Windows 10 Anniversary update'- surprise  the other day by any chance,   did you   ?
Cause that sure would explain a lot   ......

No, Windows 10 does not fit on my PC.

I was able ti fix it using the "Refresh Firefox" system. Now it's working fine...

https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

mArcb49 said

I was able ti fix it using the "Refresh Firefox" system. Now it's working fine... https://support.mozilla.org/en-US/kb/refresh-firefox-reset-add-ons-and-settings

Well done you   !!!
Now all you have to do is mark your answer as   'solved the problem',   will you do that,   please   ?