there is no setting to be notified if I am switching between secure and nonsecure websites
hello statsone, those warning messages have been totally removed in firefox 19 unfortunately - see bug #799009 (please don't post in bug reports).
for better visibility of secure pages you could use an extension like https://addons.mozilla.org/firefox/addon/safe/.
bad form to cut back on security. This makes it easier to attack a computer as now there is no warning for an unknown site.
Will check out the addon. Thanks.