I just did a clean install of the latest version, 5.45.6611. Under options>cookies>cookies to keep, there's the usual assortment of cookies I don't want or need. I moved them over to the left and manually deleted them. After restarting my computer, all came back (no surprise). I went into safe mode and deleted all and after restarting, some of the cookies returned, along with a new one that wasn't there before and joining in, the one responsible for the intrusive advertising, ipm-provider.ff.avast.com, a cookie that can never be deleted. Long story short, I had to go into safe mode four times to get rid of this junk because the cookies kept coming back. Now, I've only got ipm-provider.ff.avast.com.
Can Avast/Piriform make it any more unpleasant to use this program? Sure! They're now admitting what we've already known -- CCleaner phones home with collected data. And, they removed a privacy option to not send collected data, disabled the ability to turn off monitoring and left us with a new build that constantly runs in the background after you close the program (probably collecting even more data).
This is ludicrous. CCleaner has been turned into exactly what it's supposed to find and get rid of -- crap. I keep telling myself I'm going to dump this program if this rubbish continues. Problem is, at this point, I'm not that enthusiastic about the competition. I suppose if push comes to shove, I'll just call it a day and use Windows Disk Cleanup (better than nothing).
Rant over.