I've seen some CVEs where malicious websites induce your browser to autofill (basically steal passwords).

So the intention is that I stop some script from siphoning my passwords.

This admittedly opens me up to phishing, but to mitigate I also have containers set up for various facets of my life.

(So it's a big red flag if what's supposedly my bank doesn't open in the "bank" container".)

Edit: I also value storing the database locally versus "in the cloud"