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Window Versus Tab

Chrome: allows its users to open incognito windows, in which all tabs are
always incognito. There is no support for an incognito tab in a normal
window, and no support for a normal tab in an incognito window.

ScamBlockPlus: displays untrusted websites on incognito tabs in normal windows,
only when they are opened by clicking on a link in an email or by clicking on a link
in a post or when opened by a website that is displayed on an incognito tab.

Forever Incognito

Chrome: All tabs in an incognito window remain incognito until closed.
The incognito window also remains incognito until closed.

ScamBlockPlus: An incognito tab remains incognito until the tab navigates to
a trusted website. When navigating to a trusted website the tab becomes an
ordinary tab (is no longer incognito).

Reading Emails & Incognito

Chrome: Lets suppose that a user who owns a Gmail account wants to read emails inside an
incognito window. To do that the user must sign-into his/her Google account. The incognito
window allows the user to do that. When the user clicks on a scam-link in an email, a new
tab is opened in which the fake website is displayed. The fake page can request the user
to login with Google and to authorize the website to access his/her Gmail account. This can
cause the Google account to be compromized. The conclusion is that incognito windows can't
fully protect Chrome users from phishing scams.
Note that Chrome users can request the browser to open a link, that is displayed in a normal
window, in a new incognito window. But users don't know in advance if the link points to a
trusted or to an untrusted website. Additionally, a fake web-page that is displayed in an
incognito window can still tempt the user to input private details or to sign-into his/her
Google account.

ScamBlockPlus: Incognito tabs are better for protecting Gmail users from phishing scams.
The user reads emails in a normal window (which is not incognito). When the user clicks
on a scam-link in an email, the fake website is displayed in a new incognito tab. In that
tab the user can't login with Google, and can't enter personal or private information.