Rainer Bielefeld wrote:
on some (few) web pages I can not reach the linked contents because my
unofficial en-US SeaMonkey 2.49a1 (NT 6.1; WOW64; rv:52.0)
Gecko/20100101 Firefox/52.0 Build 20160930004545 (Default Classic
Theme) on German WIN7 64bit with my normal User Profile automatically
replaces "http" in URL by "https".
1. In Browser visit <http://www.draytek.de/>
2. In page contents heading line
ˋclick downloads - Firmwareˊ
Expected: <http://myvigoreu.draytek.com/download_de/> opens
Actual: <https://myvigoreu.draytek.com/download_de/> will
not open because it does not exist. So Error 404.
I see that after a short moment in URL bar "http" becomes replaced by
This also happens in Safe Mode without add-ons
No problem in a newly created User Profile.
So this problem seems to be caused by my preferences, but I can't find
the responsible one.
On first trying, that didn't happen for me. Visiting
<http://myvigoreu.draytek.com/download_de/> stayed on the http: version.
However, I then changed http: to https:, i.e.
<https://myvigoreu.draytek.com/download_de/>, and got a 404 Not Found
page. Now, when I try going back to the http: version, it automatically
redirects to the https: version.
Visiting the https: version returns a strict-transport-security header.
That indicates to the browser that, from now on, it should only access
that pages on that domain via https:, not http:, to protect against
attacks which attempt to force use of http:. So when you attempt to
access the page via http:, the browser instead accesses it via https:.
Since the site can serve the content in question via http: but not
https:, it looks like a misconfiguration of that site's server to me -
either it should be prepared to serve all content via https:, or it
shouldn't send a strict-transport-security header instructing the
browser to only use https:!
support-seamonkey mailing list