Update: Thanks to everyone who chimed in with suggestions. You guys are the best. I installed Malwarebytes at the recommendation of token_liberal and Galileo Humpkins and ran a scan. The scan found an adware file in my Application Support Library called “YahooEngine.xml”, as well as four other adware files. I deleted them. We’ll see if that fixed the problem. It was an intermittent problem, so I’ll have to wait a while to know, but I’m optimistic. These things mostly come as part of software install packages, I believe. So, the lesson learned is to be especially persnickety about what I install or let my girls install.

Gang, I have a problem that’s been ongoing for a while now, and I turn to you to help me fix it. My browser of choice is Safari. For a while now, my homepage on my home computer has been spontaneously changing itself to Yahoo search.

A quick search of the internet a while back told me that certain extensions can be surreptitiously installed without your knowledge (not sure how that happened) that will do this. I looked and, sure enough, there was one in my extensions folder. So I deleted it, and my homepage went back to normal. Except that it periodically switches again, and I can’t find the reason. My only guess is that there are some files in my system library that still need to be deleted, but I can’t find the answer with web searches.

So, any guesses?