Periodically, randomly, when I click "New Posts" I get taken to a mostly blank page that says the certificate for this site is expired or invalid or various errors. I click reload but get the same error. I click the back arrow button but remain on that page. My only option is to just abandon the site and try again at a later time. I don't know anything about certificates but apparently there is a problem with this one. The latest occurrence was this morning around 8. Now 2 hours later, it works again.