Update firmware on
OnePlus 8T

1. Download the latest Android 13/14 full stock ROM update from Oxygen Updater
2. Extract stock ROM using payload-dumper-go
3. Boot up LineageOS recovery
4. Go to “Advanced” -> “Enable ADB”
5. Check your DDR type using the following command: adb -d shell getprop ro.boot.ddr_type, or in case getprop returns an empty value, use: adb -d shell cat /proc/devinfo/ddr_type instead
6. Go to “Advanced” -> “Enter fastboot”
   warning

   Warning: The “Enter fastboot” option may not be present on older LineageOS recovery builds and it cannot be substituted with “Reboot to bootloader”.
7. Execute following commands:

   fastboot flash --slot=all abl abl.img
   fastboot flash --slot=all aop aop.img
   fastboot flash --slot=all bluetooth bluetooth.img
   fastboot flash --slot=all cmnlib64 cmnlib64.img
   fastboot flash --slot=all cmnlib cmnlib.img
   fastboot flash --slot=all devcfg devcfg.img
   fastboot flash --slot=all dsp dsp.img
   fastboot flash --slot=all featenabler featenabler.img
   fastboot flash --slot=all hyp hyp.img
   fastboot flash --slot=all imagefv imagefv.img
   fastboot flash --slot=all keymaster keymaster.img
   fastboot flash --slot=all logo logo.img
   fastboot flash --slot=all mdm_oem_stanvbk mdm_oem_stanvbk.img
   fastboot flash --slot=all modem modem.img
   fastboot flash --slot=all multiimgoem multiimgoem.img
   fastboot flash --slot=all qupfw qupfw.img
   fastboot flash --slot=all spunvm spunvm.img
   fastboot flash --slot=all storsec storsec.img
   fastboot flash --slot=all tz tz.img
   fastboot flash --slot=all uefisecapp uefisecapp.img
   

8. Flash correct XBL files
   warning

   Warning: Flashing wrong XBL files will brick your phone.
   • For DDR type 0 (DDR4):

     fastboot flash --slot=all xbl_config xbl_config.img
     fastboot flash --slot=all xbl xbl.img
     

   • For DDR type 1 (DDR5):

     fastboot flash --slot=all xbl_config xbl_config_lp5.img
     fastboot flash --slot=all xbl xbl_lp5.img