Leave PW. They steal from their members by using pop under windows through JavaScript and moving /mining crypto currency. Go anywhere but there! It's got nothing to do with Mcaffee. Do not trust anyone affiliated with the site. I was there for over 8+ years and I know what I'm talking about. RUN.

I suggest you try Avast. This is an excellent site for honest opinion on AVs.

https://www.tomsguide.com/us/best-antivirus,review-2588.html

I used 360 a couple of years ago and it caught nothing... ever. Installed Avast and ran it, it detected several viruses on my HD on first scan.
I also use Kaspersky online scan as a backup scanner. Kaspersky.com

Both are FREE. Avast is available at Majorgeeks or at Avast.com.

I would recommend exploring other sites rather than PW. It continuously has 'glitches' like the search problem you are having, regardless of AV you use.

I found right click 'open in new tab' function works sometimes to bypass the glitch that pops up intermittently when the LINKS to servers to watch a video simply won't connect and it throws you back to the link list over and over.
---that right click might work in your case too. Odd things happen on Primewire all the time. ''Open New tab" sometimes defeat them.

I strongly suspect Jamie V. is correct re: hidden use of your CPU to move crypto currency. (Interesting podcast recently on PBS about that).
SO----If you start hearing your CPU COOLING FAN ratcheting WAY up while on PW and you aren't doing anything to cause that, (like playing a game on another site in another window or having 10 or 15 tabs open) simply open your task mgr.
Notice fan stops almost immediately as the CPU unit slows down immediately.
SOMETHING on PW is happening in the background that shouldn't be.
BTW
[I don't care for CNET download site at all; it forces a download of an 'installer' for all programs, and I tend to think it's a 'snooper'. Ublockorigin doesn't like that site either. I recommend Majorgeeks.com--it is straightforward, has download from author's site or 2 mirrors. It has all kinds of useful software and is 100% virus/malware free.

360 may have improved, but... MS is the source... the same MS that built a backdoor into Win10 and the Dutch found it, remember? So... just sayin'.

Take off Mcaffee. It's a very bad virus software. Try 360 total security.