If you click the last item on the drop-down panel -- Change Search Settings -- Firefox will open the Search section of the Options/Preferences page. Here you can uncheck search engines that you do not want to see on the drop-down, or remove them. Other users have reported odd behavior when removing all of them, so I suggest leaving at least one in that list.

Can you get rid of the unwanted search engine?

If it comes back, one of your extensions might be the culprit. Please check the Add-ons page in that case. Either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then cast a critical eye over the list on the right side.

I have discovered there is a new section in preferences. Sorry I jumped the gun.

I clicked on Search Settings initially. It opens preferences at the 'advanced' section on the 'network tab. I did eventually discover the 'search' section of preferences. Thanks for replying.