@leocg, my profile is only about a week old--as is my Opera installation. I realize a clean profile will correct the issue, but I'd rather try to fix my current profile because I really don't want to go through the whole setup and configure exercise again for all my tabs and such. Although, I appreciate your suggestions. Thanks.
I finally solved the issue: I first tried a clean install but used my previous profile. I still had the same problem, so then I started with a fresh profile and and had to "rebuild" my windows and tabs. But now when I start Opera my tabs are loading as expected.
At least some of the forum threads are archived in the Wayback Machine ( http://www.archive.org/web/web.php }, but I've not been able to get a successful search result there for rilef's postings per se. For whatever reason his posts were deleted from these forums, they appear to be gone for good from here... I doubt Opera keeps "archive" copies of the forums, though they may have some routine periodic server backups that date back a few weeks.
I first stumbled on the deletion issue when I attempted to direct another user to a URL I'd saved referring to one of rilef's threads that answered a question this other user was asking, only to find the URL dead. That set me off on something of a quest, and I found a couple others of his URL's that were also dead. In one thread, I had been dialoguing with him about a problem solution, and a section of one of his comments that I quoted in response to him still appears if I pull up that thread, but his original post that I quoted from (plus all his other posts there) are gone from the thread. It's like a complete purge has occurred...
edit to update: In checking his profile page ( http://my.opera.com/rilef/ ), he's still listed as a member of the Community. But it appears that all his posts prior to 17 December are gone - only 11 are listed, all since then and none since 26 December. I'm guessing the purging may be something he may have done himself for some reason (perhaps major dis-satisfaction with Opera?).