Please take the time to read every step carefully. It'll explain a little bit as to the why behind some of the steps. PM me if I've missed anything.
This has been revamped as some of the steps are no longer required. Devices coming from 10.0.6 and below might have to try a different set of steps. Click here for the post with the old instructions
ADB setup and working
Global Fastboot ZIP Grab the latest version (10.0.8 as of 3/20)
Magisk Canery apk
Modded-Boot.img From here or make your own pulling your own boot.img and using magisk to create a modded boot.img file
This group of instructions are going to walk you through on how to unlock your bootloader. This is the first general step in converting your device into a global device.
1. Either follow the rules via T-Mobile (paid off and 40 days on the network) or visit this thread and get the hook up from our friend (send him some cash, for real I did this and it worked hopefully he keeps up with this for a while!). This will allow you to use the Unlock App to permanently unlock your phone.
2. Open the "Unlock" app that's preinstalled on your phone and click on Permanent Unlock. If you have completed Step One correctly, it'll congratulate you and ask you to reboot your phone.
3. Reboot your phone and Enable Developer Settings. Check out the OEM Unlock button is now able to be switched off. Switch it off.
4. Be sure to also tick USB Debugging.
5. You'll now need to submit a request for an unlock_code.bin (could also be labeled unlock_token.bin) file from OnePlus via this link. It takes a week. Seriously almost down to the second. There's no avoiding this. I've read several people try (myself included) all met with the same fate. Wait. 7 whole days. You'll get an email from OnePlus containing the unlock_code.bin file. Download this file and save it to your ADB folder.
5a. Open CMD (with admin rights) and navigate to your ADB folder. I've heard users try to use Powershell and while it works mostly, ymmv. I stick with CMD and haven't had any issues.6. Reboot your phone into fastboot--
Mine would be--
adb reboot bootloader
fastboot flash cust-unlock unlock_code.bin
fastboot oem unlock
Now that you've unlocked your bootloader, lets get to flashing the Global Rom--
7. Extract the contents of the Global Fastboot Rom zip folder directly into your ADB folder.
a. If you did this correctly your ADB folder will be filled with a bunch of new .img files. Like boot.img8. Open CMD (with admin rights) and navigate to your ADB folder. I've heard users try to use Powershell and while it works mostly, ymmv. I stick with CMD and haven't had any issues.
Mine would be--
This will also wipe your data, be sure to save anything that you need prior to running the following command.
10. You've now fully converted to the Global Firmware. Confirm this by going to settings > about phone and look at Build Number. Should say 10.0.8(as of the time of this post).
You're done! Continue on if you want to root your device...
If you're interested in root:
11. Boot the device from the modded-boot.img file to give your self temp root. Once this is done, boot the device.
adb reboot bootloader fastboot boot modded-boot.img
13. Check in the middle of the screen for "advanced options" and make sure Preserve force encryption and preserve avb 2.0/dm-verify are checked.
14. Now look under the first Magisk check and make sure that it's telling you there's an update to "Magisk" and run through that update via direct install.
15. Once that finishes it'll have you reboot the phone.
16. You've now fully converted to the Global Firmware and Rooted. Confirm this by going to settings > about phone and look at Build Number. Should say 10.0.8(as of the time of this post)
Shoutouts will go here soon.