I wouldn't fix that "bug" either. I don't want confirmation dialogs all over the place. They are annoying when I try to close or delete. Yes, I clicked close on purpose.
Google has done a good job with some of their "undo" notifications; these work much better imho.
Especially considering there's a chrome option to have the startup tabs be the tabs that were last open. No dialogs necessary, just take me back to where I was.
Which is your personal opinion. Your personal opinion is not more important than the needs of a significant portion of users.
The proper question here has to be what pisses off more users and to what degree does it piss them off: Having to click "Don't ask me again" once after a fresh installation or repeatedly losing some tabs they had opened in the background, because they forgot about them.
Google has done a good job with some of their "undo" notifications; these work much better imho.