Your reply makes me feel like nothing is really safe on the internet. Even incognito mode might not be safe. You mean some DApp, platform or Browser might not be secured enough making hackers find a way to malicious compromise users behaviour and get them expose some private information. That's strong.
But thank you for this. I learn another new thing as I've been learning here so far.
TBF, there is no 100% fool proof setup to safeguard our assets but depending on our setup, we could make it harder for the perps to come in or in a way, mitigate the risks.
I would advise you to get a hardware wallet solely for storage means and use burner wallets and/or devices (or VM,) for interacting with dapps. -- always compartmentalize risky from less risky stuff. I personally follow this and have been doing fine.