This commit is totally work in progress.
@manuhabitela the floor is yours.
If the user is logged-out, try silently log-in her every hour,
to avoid any manual login on her side.
The one hour value has been discussed with @manuhabitela, but there
is no real logic behind it. Could definitely be shorter or longer.
It needs at least to be longer than the average silent login flow
to avoid locking the user-agent in an infinite redirection loop.
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