Stack Exchange usually works flawlessly but lately I've been unable make posts – questions, answers and edits. When pressing the Submit button, Stack Exchange displays a red pop-up box saying "An error occurred submitting the ...".
After looking around a bit, I noticed that SSL was disabled on some networks on Stack Exchange, in Google Chrome displaying the "exclamation mark in circle"-symbol, representing non-private connections.
I therefore thought the problem was SSL-related. Strangely, on some network sites I get a SSL connection sometimes, but not at other times.
But even now, I'm on Meta SE with a supposedly active SSL connection (green keylock icon), and I can't submit this very question due to "An error occurred while submitting the question".
I'm using the HTTPS Everywhere extension for Chrome, so tried disabling it and Chrome antivirus plug-ins, but I'm still getting the same problem. I'm therefore not sure what the cause could be.
Are any other users having the same problem at the moment (2016-09-15–2016-09-16) or should I have other causes for concerns? I'm on a home network and there's no network administrator except me.
N.B.: There are quite a few posts on this error, but is there any consensus? There seems to be many possible problems. Will be happy to mark this question as duplicate when directed to an answer that resolves the issue.