I use Opera 63.0 with HTTPS installed. My computer is a Mac Mini using OSX 10.11.6 (El Capitan).

Something called HSTS suddenly started blocking access to many web sites today — Thursday, October 3 — with no prior warning or indication or anything. I am now unable to access some of my most important and most frequently accessed sites.
Can anyone help me?

I get this instead:

Or I get this:

@leocg
Thank you for your response.

https://www.checkadblocker.com/blog/companies-face-issues-as-lets-encrypt-root-certificate-expires/

'In his blog post, he lists clients that will break after the IdenTrust DST Root CA X3 expires. These include versions of macOS older than 10.12.1, Windows versions older than XP Service Pack 3, iOS versions older than iOS 10, OpenSSL versions less than and including 1.0.2, and Firefox versions older than 50.”

I use Mac OS 10.11.6
I wonder what I will lose updating to 10.12.1

@leocg said in Bookmark folders:

opera://bookmarks

Thank you for your response. Now I know why I never saw an option for creating bookmark folders. I click on that folder icon and nothing happens. The icons next to it are active. But not that icon. Is there anything I can do?

Mac OS 10.11.6 (El Capitan)

Version:78.0.4093.231 (x86_64)

I have many bookmarks and I can find o way to create bookmark folders to help organize them. Is there some way I am missing?

Mac OS 10.11.6 (El Capitan)

Version:78.0.4093.231 (x86_64)

https://mail.protonmail.com/login

There are suddenly numerous sites which I cannot load, including sites I visit frequently.
With some, I cannot gain access at all.

With others, if I click on “help me understand” I am given the option of proceeding to that site even though the browser deems it unsafe.
We recently switched ISP’s from AT&T to Xfinity (Comcast). This problem did not manifest right after the switch, but shortly thereafter.
If I am not given the option in “help me understand” of going to that site, I simply cannot get on. Period. And this includes a few essential web sites.
Can anyone help me?

Thanks for responding. I wondered about that because of the ereservations.att.com web site that was listed above. The situation has cleared up. If it occurs again, I will go straight to ATT.

We have DSL with AT&T. We use a router to which a few computers are linked. We don't use a VPN, if that is what you mean by a proxy.

@leocg

Thanks for responding.
I use Malwarebytes and Avast.
I received no warning from Avast while I was trying to access any web sites.
When I read you entry here, I ran Malwarebytes and came up clean.
There had been no change in any of my software settings in a long time.

Nobody have any ideas or suggestions?

I use Opera 63.0 with HTTPS installed. My computer is a Mac Mini using OSX 10.11.6 (El Capitan).

Something called HSTS suddenly started blocking access to many web sites today — Thursday, October 3 — with no prior warning or indication or anything. I am now unable to access some of my most important and most frequently accessed sites.
Can anyone help me?

I get this instead:

Or I get this:

@avl

Opera 50 crashed frequently, with no discernible pattern. In addition to that, the extension HTTPS Everywhere -- downloaded from Electronic Frontier Foundation -- which I had used in earlier versions of Opera, started going bad in Opera 50. Two or three times.
I just downloaded Opera 51. It has already crashed once. So we'll see. If it crashes again, I'll return to Opera 49 and try disabling auto-update.
If that doesn't work, I'll have to move on from Opera.
Thanks for the input.