How, exactly, does "On startup" "Continue where you left off" work?
The only info I've found on "Continue where you left off" is vague, stating something like, "it starts where you left off" and addresses crashes. Well, that doesn't tell me whether or not my work will be saved and restored when I continue in the following scenario:
I have multiple Opera windows open, each with multiple tabs open (some with lots and lots of tabs open). Now, I need to restart my computer. What happens? The general explanation (you'll resume where you left off) is ambiguous in that it fails to specify what "where you left off" means. In my case, does it mean the last Opera window the OS closed on its way to a normal shut down followed by an automatic reboot? or does it mean the collection of windows that were open when the OS started shutting down? The answer is critical.
I know it works in a crash recovery because currently I manually kill each window and upon restart, they're all there. I highly suspect it will work during a normal shutdown. But, would like to hear from someone who definitely knows.
I tried searching "on restart" here (with and without quotes), but the search just kicks me back to the forum top page. I tried searching on "restart" and got too many irrelevant pages.
It reopens the same pages you had open, and each tab has the same history (back and forward) as it had before ... well, except private tabs which are of course forgotten. Opera does not remember data that you entered (unless the website does that itself, such as Google Docs or Windows Live).
If you are that worried about it then get a session manager. Session Buddy is the best one I have ever used. You will need another extension named "Download Chrome Extension" to use it in Opera, though.
except private tabs
Private tabs are no longer a thing. It's only private windows now.