Accessing non HTTPS connections with Firefox

Problem

Depending on custom browser settings Firefox redirects from http to http**s** automatically.

Solution

The simplest solution is to check that no bookmarks are saved for your domain http**s**://... (e.g., for https://webengineering.ins.hs-anhalt.de).

If this does not solve the problem, then you have to try some changes to your browser settings.

• clear site preferences
  • go to Options -> Privacy & Security -> History
  • click on Clear History
  • check Site Preferences
  • click OK
• go to about:config in your address bar and see if any of the following setting resolve the problem:
  • set network.stricttransportsecurity.preloadlist to false
  • set browser.fixup.fallback-to-https to false

For more information and possible solutions see:

• this Stack Overflow question about Firefox redirect
• the official Mozilla support page for this issue