Depends on what you are trying to do. Burner device, running an Emulator, with mic and camera physically disabled, as well as Bluetooth and ANT antennae physically disabled. Run your browser in the emulator/virtual machine. Use any WiFi other than your own. Don't use your name on anything. Anything. Change your identity to John Smith or Jose Garcia. Don't use the same password on anything. Don't use the same username on anything. If it needs a phone number, get a burner phone, then ditch the number. Devices talk to each other. Without your consent. This is why it doesn't take long for a device to figure out who you and your friends are for contact tracing. Spoof your GPS location. Spoof your MAC address. Use Peerblock or equivalent and blacklist everything. Then, start, to slowly allow connections as needed. If you are too locked down and too anonymous, you will not be able to use any services. Not even Google will let you search in some cases. This is why you need multiple fake online identities. The truth is Chrome and Firefox, with their plug-ins and extensions, are the best browsers, utility wise. You need plug-ins like ublock Origin, Ghostery, Decentraleyes, etc. You are the product. Your data is being traded among hidden powers that are using it to social engineer totalitarianism into everyone's lives. The only real way to know what data is flying around is to start tracking packets and running down their source and destination. Most people will find virtual devices, like virtual USB and virtual modems inside your modem. All of your devices are communicating with each other, if they are modern and recent. They are wholesale saving up your data, then sending it off through a tunnel made by your ISP, to marketing firms, which then sell it. In one instance, I found someone's TV acting as a storage device, that was uploading data gathered by the TV. It is very difficult to eliminate all the threats.