kartikoli
Innovator
I use FF for personal use only and don't like login to gmail so it doesn't sync my activities to gmail but I did get adds on mobile so the only logical reason I could come up is gmail.Private mode doesn’t save cookies, so hardly any chance of that happening unless you login every time and then surf.
This is of course a bad change from Firefox but it more alarming that people raise this in context of using Google and Microsoft products that are basically data mining the hell out of your device.
I use Brave for work purpose and it does the job but can't say it does what I tell it like my settings says to remove all logins and data when I close browser which it does but I can still see similar recommendations on youtube from previous login session (correct me if its due to youtube sensing private mode of brave from same IP/Computer? )