im in the same boat. I have tried 6 different browsers. Im on Mac 10.11. It happens on most websites.
I have cleared cache on all browsers
2) cleared cache on the machine
some sites give the option "proceed (unsafe)"
other sites do not even allow that.
a "hack" is type "thisisinsafe" which seems to bypass this error. If not reload and try again, usually works.
worst case, I open another browser and try the same thing. You can get in but its really annoying. I would go so far as to suspect this is some form of internet censorship since it is happening across teh board and does not seem to be specific to one browser, website or machine. I have even contacted my service provider who claims everything is cool on their side.
a small percentage will jump though the hoops and loops to get through to the websites. Maybe this is what they are hoping that most will just give up.

there appears to be no way to delete search engines or add new ones. One of the search engines is amazon... really?

there are so many other better search engines out there it would be great to be able to use them and replace things like ddg, google and "amazon" what's up with that? Who uses amazon as a search engine?

hi I read where there's a problem with the vpn. Its been a few days, wondering when it will be coming back? Will you be adding new IP addresses? Many times I get "your IP is on a spam list" and the website is blocked.

secondly, is there anyway to add a default search engine besides the ones on the menu?

there appears to be no way to delete search engines or add new ones. One of the search engines is amazon... really?

there are so many other better search engines out there it would be great to be able to use them and replace things like ddg, google and "amazon" what's up with that? Who uses amazon as a search engine?

@leocg thanks I suspected this. Nothing but problems with this co. so far. "Hostpapa"

trying to edit my website, logging in as admin I get "Your IP is listed as Spam".
I've switched the vpn, Europe, Asia, America, Optimum location but always get the same thing. is there any way to have more IP addresses to chose form? How do you get your IP off such blacklists?

@temminckiiii crossing fingers but I think this worked! It was a matter of downloading a new certificate and setting it to "always allow". The new certificate does not expire until 2035. So far Ive only tried a few sites but they have worked. I can't thank you enough! So simple but to hard to find this needle in the haystack!

@temminckiiii unbelievable! Thank you! This is the first light I have seen in this tunnel! Have not gone through the whole article yet but Im excited that this may be the solution as it seems to be a machine problem, not the websites or browsers.

You wouldn't believe how many places Ive been inquiring about this problem and so far no solutions. I hope this is it. Thanks for your reply!

@twoboots

I thought the certificate was a function of the websites you were visiting? Are you saying you downloaded something onto your computer that allows you to visit the sites?

im in the same boat. I have tried 6 different browsers. Im on Mac 10.11. It happens on most websites.
I have cleared cache on all browsers
2) cleared cache on the machine
some sites give the option "proceed (unsafe)"
other sites do not even allow that.
a "hack" is type "thisisinsafe" which seems to bypass this error. If not reload and try again, usually works.
worst case, I open another browser and try the same thing. You can get in but its really annoying. I would go so far as to suspect this is some form of internet censorship since it is happening across teh board and does not seem to be specific to one browser, website or machine. I have even contacted my service provider who claims everything is cool on their side.
a small percentage will jump though the hoops and loops to get through to the websites. Maybe this is what they are hoping that most will just give up.

@leocg well isn't that interesting!? on your suggestion, I checked a few sites;

bitchute.com - no previews
youtube.com - previews come in!
rumble.com - no previews
https://www.brighteon.com/ - previews come in!

I got this error on peertube.org'

Your connection is not private
Attackers might be trying to steal your information from joinpeertube.org (for example, passwords, messages, or credit cards).

NET::ERR_CERT_DATE_INVALID
Help me understand
joinpeertube.org normally uses encryption to protect your information. When Opera tried to connect to joinpeertube.org this time, the website sent back unusual and incorrect credentials. This may happen when an attacker is trying to pretend to be joinpeertube.org, or a Wi-Fi sign-in screen has interrupted the connection. Your information is still secure because Opera stopped the connection before any data was exchanged.

You cannot visit joinpeertube.org right now because the website uses HSTS. Network errors and attacks are usually temporary, so this page will probably work later.

https://www.ted.com/ = no previews

so I guess its hit and miss

@leocg

-- I tried disabling trackers and blockers, refreshed the page, still no preview.
-- Changed the VPN, refreshed, still no preview.
-- also cleared cache, no difference.