Tap on or Build Number seven times until you see a message saying "You are now a developer."
Two hours of frantic Googling later, buried in a Reddit thread with three upvotes, a former mobile store employee wrote: *“On some OPPO models, dial #8011# and look for ‘Demo Mode Off’ in Engineer Mode.” It felt like an urban legend. oppo demo mode remove
There are several ways to exit this mode, ranging from simple menu toggles to hard factory resets. Tap on or Build Number seven times until