I want to switch back to iOS12.3 from iOS 13.
For this apple support says that It can be done by restoring backup from iTunes:
But iTunes is not installed on my Ubuntu computer. so How to switch back to original iOS from iCloud backup?
One crude way I understand, is to format iPhone and this will turn phone into new one, then I can restore the backup from iCloud. Will formatting the iPhone restore the iOS 12.3 ?
Edit: I erased everything, and restarted as new iphone/also restored from very old icloud backup. But phone didn't switch back to iOS12.3.