What URL causes this error? No developer can troubleshoot a bug if you can't tell them how to reproduce it. https://www.google.com and https://opera.com load without error for me in 23.0.2254.11474

Yes you're right, the problem is that the URL is on a server at home behind a slow connection and I prefer to not post the URL in public.

So I've set up a webserver on a VPS with the same configuration. It uses a self-signed key.
The address is: URL. Opening the page may give a security warning because of the self-signed key.

I've been using Opera Mini (Stable & Beta) for many years.

Somewhere between the stable-22.0.2254.113472 and stable-23.0.2254.114353 something has changed that causes a net::ERR_TOO_MANY_REDIRECTS message when visiting a secure page (https).
The older version has no problem, but the newer version will show this error message when not in extreme mode (data saving on Wi-Fi is turned on and I'm on Wi-Fi).

The same also happens between beta-23.0.2254.114097 and beta-23.0.2254.114298.

The few other browsers I've tried on mobile (Android's default browser) and desktop (Chromium and Firefox on Linux) has no problem with this page.

I'm missing the feature to open speed dial links in a private tab.