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Different web browsers behave differently when asked to automatically log in to web sites. Variously, they range from complete prohibition of the practice to permitting it only if certain system parameters are configured.
e.g. Chrome + Firefox have plugins that allow auto login :-
Chrome - Auto Login
https://chrome.google.com/webstore/detail/auto-login/kjdgohfkopafhjmmlbojhaabfpndllgk?hl=en
Firefox - Auto Auth
https://addons.mozilla.org/en-GB/firefox/addon/autoauth/
Specifics
In this article, details of how to allow automatic logging-in to a web page concerns the Microsoft Internet Explorer (version 6 and above) browsers only. Please consult your browser documentation for a solution related to your own choice of browser.
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