Downgrade Oneplus 9 To Android 11 [portable]

Android 12/13 hides the "Local Upgrade" option. You need to install a helper app:

This method is for functional devices running OxygenOS 12, 13, or 14. Download Files Android 11 Rollback Package OnePlus Local Update APK from the official OnePlus Community Rename Extensions If the rollback file ends in , rename it to end in If the local update tool ends in , rename it to end in Place Files : Move the rollback root directory of your phone's internal storage (not inside any folder). Install Tool : Install the Local Update APK and open it. Run Downgrade in the top right. Select the rollback file you moved to your storage. Confirm the warning that your data will be wiped. : Once finished, tap Downgrade Oneplus 9 To Android 11

Outside, the world had moved on to Android 14. But Leo didn't care. He turned off system updates forever. On his home screen, a small widget read: Android 12/13 hides the "Local Upgrade" option

: Ensure all photos, messages, and files are backed up to a cloud service like Google Photos or an external drive. Battery Level : Keep your device charged above to avoid power failure during the flash. Remove Security Install Tool : Install the Local Update APK and open it