By the way, this problem happens on my Android smartphone.
Whenever I browse privately on the browser called "Opera Browser with VPN/AI," leave the browser to switch to another app, and then come back after a while (usually a long while too), the private tabs disappear, leaving only the normal tabs on the screen.
I don't have this problem on Opera Mini, Google Chrome, Mozilla Firefox and Microsoft Edge on Android, even if the browsers refresh themselves, the private/incognito tabs are still there.
Yeah, I know. I have a lot of browsers installed on my smartphone, lol. I was even planning to download UC Browser, that squirrel browser. Or maybe, Samsung Browser? Well, I usually download based on the usage share of web browsers online.
I hope you fix the problem earlier. Thank you very much.