>> If it doesn't return after installing a different version, why would it matter... or do you mean something else? Just
>> continue keeping an eye on that security icon (which you indicate you do anyhow)... as you've already seen, if
>> something is amiss with Opera being able to connect securely, it will let you know.
Yes, I sort of mean something else, though I do understand what you're saying. I'll try to clarify.
It's counterintuitive. The instinct is to try one thing after another until the problem goes away and then consider it solved. But the best thing to do first is the opposite -- be able to reproduce it on demand.
Suppose I try something and the problem goes away. If the problem shows itself again, I know for sure it wasn't solved. But if it doesn't show, is it solved? Maybe it just won't show for a week. Or months. When I cleared out the data, the problem did indeed go away for a week, but it wasn't solved. Another example: The date on my 12.01 download is August of 2012, and my query in the forum was in January of 2014. The problem didn't show for well over a year, but it existed all that time.
Yes, I can keep my eye on the security icon, but humans are bad at maintaining vigilance watching for something rare. That's why personnel at security checkpoints routinely fail field tests. They're not incompetent. Humans just aren't suited for that kind of job. In fact, my problem may have happened sporadically during the year and a half before I noticed it, despite the fact that I am good at watching for security problems.
Now, suppose instead of trying things until I no longer see the problem, I first find out how to reproduce it and turn it off at will. Then I apply a solution. Right away, I try to reproduce the problem. If I can (and I confirm it by using my verified method for turning it off), I know it's not fixed. If I can't, then I know the problem is fixed -- not just that it hasn't shown itself yet. It's really fixed. Note that once I try a possible permanent solution without knowing how to test it, I forfeit being able to know for sure that it actually got rid of the problem. Not to mention the obvious fact that knowing how to trigger a problem may be all I need to know in order to prevent it.
Still, after all the wordiness, I may eventually decide not to spend more time on the problem. But I'm in no hurry. I'm not painted into a corner and desperate. I have plenty of alternatives. And I can switch strategies any time I want. I may decide not to bother further, and just upgrade and hope for the best. If my choice affected others, that would be irresponsible, but as it is, it's just my problem.
I hope this is clearer than my previous post. Thanks to those who have looked at the problem, and especially those who have responded.