When I use Mullvad to do searches on internet on a device, after few hours, all my searches turn up as video subjects shown in my Tiktok account on another device. Please explain how.
Vpn only change your ip, they can decouple you from some services or your ISP.
But they don’t prevent other forms of tracking.
Some vpn bundle anti tracking features like adblocker but this also doesn’t solve all ways.
There’s tons and tons of ways to verify “you” are “you”
Unique identifiers, fingerprinting, canvas fingerprinting, tracking cookies, staying logged into Google, not deleting cookies automatically as soon as we pages close, not using a privacy friendly browser and so on.
Tons of ways to identify you.
So your next step would be to use a privacy focused browser on your preference.
Brave ( Chrome based)
Heavily tweaked Firefox
Librewolf ( Firefox based)
Mullvad Browser ( Firefox based)
Each Browser still can utilize some useful extensions.
But also don’t do too many extensions that’s can be also one unique identifier about you and fingerprinting.
Like any other VPN, mullvad only changes your IP address.
It does not prevent any kind of cross-tracking that apps can do.
Have your ever read the Eula for TikTok? I can’t believe anyone would install or even use that app
The Apple App Store data linked to you, I mean wow
Cookies don’t care about your IP. You’re probably signed on with your google account or something.
you are logged with the same account? I mean, are you using google? are you logged in in the google? like logged in your gmail? if you are logged in in any way to a search service, they are tracking you, and you are using tik tok with the same email or something similar? then you are being tracked and they know exactly who you are, no matter of having VPN or not.
if you want to use these services like google, tiktok or whatsoever, you’ll need to do some kind of strategy so they don’t track you somehow.
for example, if you like youtube videos and don’t want to get tracked, you can use piped, new piped or libretube. Use a search engine that don’t track you, like duck duck go, email? go to proton mail, and so on.
I reccomend this for you if you want more privacy: Best Privacy Tools in 2022: Software Alternatives
are you logged in in both devices? that’s all they need to identify you
also, your phone is constantly “listening” everything around, if you have your phone constantly with you everywhere you go, then everything that it “hears” will be used to profile you and send you advertising
you can’t have any privacy if you have your phone 24/7 in your pocket. period.
Uninstall TikTok. They make you agree to access to basically all of the data on, not just the installation device, but all other devices you own
They are on different devices. Firefox has adblocking and ub origin and other so called privacy extensions and vpn promises privacy also, yet it seems to fail to deliver on such promise.
Nope. Browser is on Mac. Tiktok is on android.
Brave is a great and awesome privacy browser rivaling librewolf in the amount of data sent out from the browser and anti fingerprinting.
Fun fact:
The dudes who created Javascript in ten days, cofounded Mozilla Firefox, and are CEO of Brave, are the same guy!
aka Brendan Eich
You clearly don’t understand the scope of what a VPN can provide. A VPN can not change the fact that just about every website out there will collect as much information as possible on you, especially search engines. You don’t happen to have used google to do those searches?
well try your system and see
If you need a browser with log in, I can recommend ublock origin with all of the filter lists turned on + j-shelter and canvas blocker for normal browsing, outside of mullvad browser which is for everything outside login and where additional addons are counter productive.
test your adblock while you’re at it
as soon as you log in, your anonymity is gone
Do you use same accounts on both devices? Sync?
your android has a playstore app right? this app is using your email for login. tiktok knows that. if you use any browser like chrome, safari, you are being tracked and if you logged in in the same gmail account ever, they can do a match that your accounts are the same. the tracking mechanisms are crazy these days, for instance if you log in in a wifi connection with the same devices, this is tracked and correlated as well. so it is a line very thin where you can skip from being tracked.
thank you for the very useful links 
No and I have never installed TikTok on my computer.
Nope, not sure why you Compare this also.
Brave is proven as safe as librewolf ( or close to) and safer than a heavily tweaked Firefox
The OP was about Firefox having some sort of unusual monopoly on privacy. I guess my post has become an unintentional IQ test