Can any web sites read (steal) my Google/Microsoft/Yahoo/AOL account's user name or password?

I have a habit of logging in to my accounts for web-based email access and then using the same browser to surf the Internet for both personal and work. So this browser can be logged in to emails (e.g. Gmail), internet banking sites, shopping/commerce sites (e.g. Amazon), social media sites (e.g. Twitter.com, Facebook.com), probably identified by session IDs, cookies or what's not.

I understand that by default all web sites are prevented by the web browser from snooping on …

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