For some sites, HTTPS by Default does not work

Example: in private mode, enter in the address bar

Result: Firefox queries instead of

See also:

It is a little confusing because there is an https-first feature without a UI and an HTTPS Only feature with a UI. To confirm that https-first is enabled for private windows, you can check these preferences:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

(2) In the search box in the page, type or paste and pause while the list is filtered

By default:

  • => false
  • => true (for private windows)

Testing in Firefox 93.0 with the default settings, if I open the Network Monitor before submitting an address, for the Network Monitor shows was requested in a private window. I don’t see a different behavior with the site. However, perhaps there is a DNS-related or other explanation for differences among Firefox installations??

Thank you for your answer. Attached is a screenshot of the Network Monitor after requesting

Normally, requesting in a regular window returns a 301 redirect to so what you are seeing (403 forbidden) doesn’t match any normal Firefox behavior. Could you test bypassing your add-ons by restarting in Troubleshoot Mode? See:

Attached is the same screenshot in Troubleshoot Mode (but on a higher-resolution screen). It looks the same. Maybe the problem comes from some kind of geoblocking on behalf of Publix (I’m not in the US). I don’t want to take more of your time…

I can’t reproduce the Publix problem, so perhaps you are right that there is a block?

An example came up on Reddit yesterday of a site that has a redirect for the HTTPS request that it does not have for the HTTP request, so HTTPS First takes Firefox to a dead end:

For Publix, I get this in the Browser Console (sitting in California):