... Opera ... started to balk at many pages I need to use daily with the "weak ephemeral Diffie-Hellman public key" error.
Opera has become unusable for me after last update. I don't understand why this isn't getting fixed.
See the thread https://forums.opera.com/topic/10383/how-to-disable-weak-ephemeral-diffie-hellman-public-key-error and my comment at: https://forums.opera.com/post/78384