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[Solved] Official Oxygen OS 5.0 boot loop problem for rooted users

Update: A working solution is listed below for reference.
A detailed tutorial for encrypted and rooted Nougat OOS users on how to flash Oreo OxygenOS without running into the infamous boot loop issue.
Step 1: Remove all fingerprint & pin from the device
Step 2: Backup everything on your PC/Laptop
Step 3: Reboot the device to TWRP bootloader
Step 4: Using a PC/Laptop, flash Blu_Spark TWRP via ADB command
Step 5: Reboot device to TWRP
Step 6: Wipe dalvik, cache, system & internal partition
Step 7: Format device
Step 8: Copy Oreo Rom & no_verity_mod file onto your device
Step 9: Flash Oreo under TWRP
Step 10: Flash TWRP again
Step 11: Reboot to recovery again
Step 12: Flash Magisk Beta for root (I used Magisk beta 14.5)
Step 13: Flash no_verity_mod file
Step 14: Reboot into Oreo Oxygen OS
Your device is now decrypted, rooted and running the latest stable Oreo OxygenOS build.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Seeing as a couple of forum members have messaged me regarding the official update of Android Oreo, I would like to make a proper discussion thread for it.
I just want to make it clear that HatRiGt has made an outstanding effort by making a tutorial thread. -> ([OFFICIAL] [Stable Oreo 8 ] Oxygen OS 5.0 Update [Tutorial-Root] [Mirror] by HatRiGt)
With that said, I believe the title is somewhat misleading. Since a lot of members are under the impression that this Oreo update will be a simple and straightforward process like all previous Nougat updates, except for it's not.
Stock OxygenOS
Rooted with Magisk v14
TWRP Recovery
Device already encrypted
Almost everyone with the device configuration listed above has run into some sort of serious issues, such as boot loop, file system decrypted/corrupted, or a complete data loss.
So far, it seems like the few groups of members that have managed to update their device without any data loss are either users that have flashed the Oreo Beta rom, or users with a non-rooted & stock recovery device. Almost everyone else is facing some form of issues.
I understand that some people have suggested that rooted users should first format the internal storage, before proceeding with the Oreo update. I personally feel that it is an inconvenient method of OS update, since many of us have a huge collection of photos, media files and app settings etc... to worry about.
The purpose of this thread is to address the aforementioned problem for rooted OOS users and to come up with a solution, so that everyone can enjoy this latest stable release of Android Oreo.
Any comments or thoughts are welcomed.

Maybe a stupid idea, but I am a bit noobish in this. Running stock 4.5.15, rooted, K2 TWRP and Magisk.
Is it not an option to just flash stock recovery (via ADB or Root Toolcase), then remove/deinstall Magisk and use the OTA update? After that flash Blue Spark via ADB, reflash Magisk and be good to go?
Unfortunately this is my daily driver company phone so I haven't the time to experiment with it at the moment.

I had some issues trying to dirty flash mine. Didn't know about others' troubles until after the fact.
I ended up with the black screen and blue notification LED. Everything encrypted and unable to go anywhere in recovery mode. Had to do a full wipe and image load; I also am not sure if I had been running my backups for a while, so this could be a lesson learned.

Malcol13 said:
I had some issues trying to dirty flash mine. Didn't know about others' troubles until after the fact.
I ended up with the black screen and blue notification LED. Everything encrypted and unable to go anywhere in recovery mode. Had to do a full wipe and image load; I also am not sure if I had been running my backups for a while, so this could be a lesson learned.
Click to expand...
Click to collapse
Still experiencing the exact same problem.
The problem is, I can't transfer the zip to my phone to flash.
Under TWRP, any computer recognizes it as a mass storage, but even with adb push/sideload it doesn't work.
Does a full wipe help with that problem?

DionysosD said:
Still experiencing the exact same problem.
The problem is, I can't transfer the zip to my phone to flash.
Under TWRP, any computer recognizes it as a mass storage, but even with adb push/sideload it doesn't work.
Does a full wipe help with that problem?
Click to expand...
Click to collapse
I saw the same thing. Unable to copy the zip file until I did the full wipe, which means no chance of recovering what was on it, but I'm cutting my losses.
I'm now stuck on the configuration stage, it's just sitting on "Just a sec..." for forever it would seem. Trying to update on Christmas day was a bad decision.

Root *shouldn't* cause issues. But that really depends on what has been changed by root
Twrp will though.
Flashing stock recovery should allow the ota to work without issues.
Having said that it's a major update so factory reset isn't a bad idea anyway.

fards said:
Root *shouldn't* cause issues. But that really depends on what has been changed by root
Twrp will though.
Flashing stock recovery should allow the ota to work without issues.
Having said that it's a major update so factory reset isn't a bad idea anyway.
Click to expand...
Click to collapse
I had the same idea, encrypted, rooted (no system modifications) and running twrp, I flashed stock OP5 recovery, and updated through the ota and ended up in a bootloop.
I did a nandroid to a usb before updating, but I still lost all internal storage files

so...the no verity is only for decrypted users right?

fards said:
Flashing stock recovery should allow the ota to work without issues.
Having said that it's a major update so factory reset isn't a bad idea anyway.
Click to expand...
Click to collapse
I appreciated the suggestion, but there are a lot of users with loads of files stored on the device, along with various other app settings, having to wipe the storage or perform a factory reset can be really troublesome. I believe that OnePlus pushed through this stable OTA update with the intention of a seamless update. Endless boot loops and data loss wouldn't be an ideal method of an OS update.

The way I installed the beta 2, was removing the pin and fingerprint before installing magisk through Twrp, at first I got stuck with bootloop, but made it come back to life after installing the ota through Twrp and booting back, removing my pin and then installing magisk.

igoorsoouza said:
The way I installed the beta 2, was removing the pin and fingerprint before installing magisk through Twrp, at first I got stuck with bootloop, but made it come back to life after installing the ota through Twrp and booting back, removing my pin and then installing magisk.
Click to expand...
Click to collapse
Okay, so I've been thinking that maybe it's possible for us rooted Nougat OOS users to update to Oreo stable release without any form of data loss.
I've listed the steps to avoid any potential confusions.
You start with stock Nougat OxygenOS (Encrypted) with Magisk v14 (root) and non-Oreo compatible TWRP (e.g TWRP 3.1.1.1)
Flash an Oreo compatible TWRP (e.g Blu_Spark TWRP)
Boot up the new Oreo compatible TWRP
Flash OreoBeta 2
The phone should boot up OreoBeta 2 without any data loss
Dirty flash the official Oreo stable release via the new Oreo compatible TWRP
Flash Oreo compatible TWRP again
Flash Magisk beta for root access
Flash No-verity file
So the basic order of flashing should be Nougat OOS -> OreoBeta -> Oreo Stable
Any thoughts on this?

Are you sure flashing Open beta2 won't compromise the internal storage? I bet no one affords to loose previous photos, apps, settings, etc without full backup.

I've triyed this. All good till i flash 5.0 & Magisk & no verity....

Hello there and Merry Christmas.
I faced to this issue too, fortunately before to update to Oreo. I made a full backup of my data.
My OP5 was running under Oxygen OS 4.5.15 Nougat 7.1.1
Rooted with Magisk V14.5
TWRP Blue_Spark 3.1.1
First I have updated my TWRP to Blue_Spark 3.2
And then I've installed Oreo Oxygen OS 5.0 from TWRP with the full zip.
After the update, my op5 has been bricked and locked on blank black screen with a blue led.
To unbrick my phone I used a tiers softwate to install Hydrogen OS first.
After that I could installed TWRP Blue_Spark 3.2 and then flash to the full zip Oreo Oxygen OS 5.0
My OP5 works as well but...
Right now I'm blocked, Google who usually sends an SMS, does not offer me. Only the authentificatorator or the security code. : /
Be careful, print a Google code to access your account when you go to install Oreo.
I'm waiting for Google to do the right thing.

Hi,
I have a boot loop on my OP5.
I ddirty flashed Oreo and had twrp/magisk.
Any ideas to recover my data partition ? (I had fingerprint/pin)
Best regards,

1) What is that "no-verity" file?
2) Isn't the regular TWRP 3.2.0 good with Oreo?

MadCow809 said:
Okay, so I've been thinking that maybe it's possible for us rooted Nougat OOS users to update to Oreo stable release without any form of data loss.
I've listed the steps to avoid any potential confusions.
You start with stock Nougat OxygenOS (Encrypted) with Magisk v14 (root) and non-Oreo compatible TWRP (e.g TWRP 3.1.1.1)
Flash an Oreo compatible TWRP (e.g Blu_Spark TWRP)
Boot up the new Oreo compatible TWRP
Flash OreoBeta 2
The phone should boot up OreoBeta 2 without any data loss
Dirty flash the official Oreo stable release via the new Oreo compatible TWRP
Flash Oreo compatible TWRP again
Flash Magisk beta for root access
Flash No-verity file
So the basic order of flashing should be Nougat OOS -> OreoBeta -> Oreo Stable
Any thoughts on this?
Click to expand...
Click to collapse
Isn't a full wipe required even for Oreo Beta builds? Also thanks for starting this thread I'm really eager to jump into Oreo but would love it if no wipe happened.

BenSow said:
Isn't a full wipe required even for Oreo Beta builds? Also thanks for starting this thread I'm really eager to jump into Oreo but would love it if no wipe happened.
Click to expand...
Click to collapse
I think it's possible to flash the Oreo Beta without a full wipe. And yeah, I've got way too much stuff on my device, so I can't afford to wipe my storage.

MadCow809 said:
I appreciated the suggestion, but there are a lot of users with loads of files stored on the device, along with various other app settings, having to wipe the storage or perform a factory reset can be really troublesome. I believe that OnePlus pushed through this stable OTA update with the intention of a seamless update. Endless boot loops and data loss wouldn't be an ideal method of an OS update.
Click to expand...
Click to collapse
I never suggested either.
Oneplus don't test using twrp or using root.
Their prescribed ota route, as pretty much every other OEM, is unmodified system partition using stock bootloader.
Twrp or root will affect those and can cause bootloops.
Obviously there's a chance with so much diversity in installs that there can be an issue arises.

raboliot said:
Hi,
I have a boot loop on my OP5.
I ddirty flashed Oreo and had twrp/magisk.
Any ideas to recover my data partition ? (I had fingerprint/pin)
Best regards,
Click to expand...
Click to collapse
https://forum.xda-developers.com/oneplus-5/how-to/guide-restore-data-stuck-bootloop-n-o-t3724515
Read it all.
I have a Encrypted phone and I was able to recover all.
Actually I was able to restore my Nandroid backup.

Flash oxygen os 5.0.5 on OP3T with magisk using TWRP ??

Hello friends..(I am a noob )
Actually I was running on Oreo 8.1 lineage os 15.1 but then I wanted to flash oxygen os 5.0.5 stable ROM I searched for the thread on XDA and then followed it..
Here is what happened:-
1---First I clean flashed the ROM (oxygen os) using TWRP 3.2.3-0 successfully..
But then when I tried flashing magisk 17.1 my phone RESTARTED in between of magisk installation process...??
2--Then I tried it using Blu spark recovery
The same issue occured..
3-- then I tried flashing firmware 1st then OOS
Same issue occurred now my phone vibrated vigorously..
4--when I tried to just flash OOS
It again restarted...
5--Now I want to know how can I flash oxygen os with magisk using TWRP recovery ????
I had tried this process using magisk 14.3, 16,17,17.1
But none worked
Plz help me..

I always use bluespark recovery, I have flashed all Oxygen updates and magisk and never had such problems.
The restart is happening suddenly,in the middle of the flash or after it has finished?
Sent from my ONEPLUS A3003 using Tapatalk

RASTAVIPER said:
I always use bluespark recovery, I have flashed all Oxygen updates and magisk and never had such problems.
The restart is happening suddenly,in the middle of the flash or after it has finished?
Click to expand...
Click to collapse
Happening in between..??

Mayank7 said:
Happening in between..??
Click to expand...
Click to collapse
Can u pls elaborate..
How did u flash OOS using Blu spark ??

2 days ago I just did the same (flash firmware, OOS 5.0.5 stable then magisk using TWRP 3.2.3)
At first I flashed magisk v16, then updated to v17, and here's where I encountered a problem, it keeps boot looping at the boot animation
But I solved it by just wiping data and repeat flashing the ROM & everything else
Just make sure none of the files are corrupt I guess, and wipe clean everything including internal storage (after backing up)

deetailed said:
2 days ago I just did the same (flash firmware, OOS 5.0.5 stable then magisk using TWRP 3.2.3)
At first I flashed magisk v16, then updated to v17, and here's where I encountered a problem, it keeps boot looping at the boot animation
But I solved it by just wiping data and repeat flashing the ROM & everything else
Just make sure none of the files are corrupt I guess, and wipe clean everything including internal storage (after backing up)
Click to expand...
Click to collapse
There is no reason to wipe internal files during flashing of new roms and Magisk latest version is 17.1, not 17 which was causing bootloops.
So your post is totally wrong and better next time be careful of what you are writing.
Sent from my ONEPLUS A3003 using Tapatalk

RASTAVIPER said:
There is no reason to wipe internal files during flashing of new roms and Magisk latest version is 17.1, not 17 which was causing bootloops.
So your post is totally wrong and better next time be careful of what you are writing.
Sent from my ONEPLUS A3003 using Tapatalk
Click to expand...
Click to collapse
OP said something about a clean flash, so he probably already cleared his data. So it shouldn't be a big deal if he does it again.
When changing from LOS to OOS you should always clear data anyway.

I think you might not be wiping everything before flashing. If you have a computer, I would follow this steps (assuming that you already backed up all your photos, documents, etc):
1- Download the factory image to your PC
2- Wipe EVERYTHING in twrp (through the advanced option)
3- Reboot to recovery
4- Connect your phone to the PC and send the factory image zip to the phone just like with any other usb drive.
5- Flash the file through twrp and inmeadiately flash latest magisk
6- Reboot to recovery and do a factory reset through twrp.
7- Reboot and be happy.
One or more of those steps might be unnecesary, but I always do it like that and it always works...
Have fun!

How to unroot and lock bootloader on OOS 5.0.5?

Is there any alternative method to lock bootloader and unroot the device? I have read other topics that it will required to flash back to 4.0.1 version and install stock recovery.
Possible to have adb lock bootloader and reflash latest OOS 5.0.5 without flashing Magisk module?
Sent from my [device_name] using XDA-Developers Legacy app

Switched last week from Pixel Experience 9.0 (unencrypted) to OOS 5.0.5 and locked the bootloader.
Flashed the latest OOS from TWRP (with all wipes done before);
Waited for the phone to boot OOS 5.0.5 once - without root the TWRP is gone ,replaced with stock recovery;
Rebooted to stock recovery and performed another factory reset;
Waited for the phone to boot OOS 5.0.5 again (to be sure everything it's fine);
Rebooted to bootloader (fastboot) and executed: fastboot oem lock command;
Done!
P.S. - Backup your files before any wipe or bootloader re-lock.

[d]amour said:
Is there any alternative method to lock bootloader and unroot the device? I have read other topics that it will required to flash back to 4.0.1 version and install stock recovery.
Click to expand...
Click to collapse
Do what the previous response says. Just flash the 5.0.5 full zip, reboot to wipe TWRP. Then relock bootloader.
I suspect the only reason the guide you mention, says to flash 4.0.1, is because the guide is old, and 4.0.1 was just the latest version at the time. There isn't any requirement to "downgrade" to an older version, to return to stock/unrooted/locked bootloader.

lesbianu said:
Switched last week from Pixel Experience 9.0 (unencrypted) to OOS 5.0.5 and locked the bootloader.
Flashed the latest OOS from TWRP (with all wipes done before);
Waited for the phone to boot OOS 5.0.5 once - without root the TWRP is gone ,replaced with stock recovery;
Rebooted to stock recovery and performed another factory reset;
Waited for the phone to boot OOS 5.0.5 again (to be sure everything it's fine);
Rebooted to bootloader (fastboot) and executed: fastboot oem lock command;
Done!
P.S. - Backup your files before any wipe or bootloader re-lock.
Click to expand...
Click to collapse
Didn't you face DM-verity warning?
If yes, then how you removed it:-by
"ADB sideload" command or by any other means?
Please specify..........

If I had extra problems, for sure I would warn you about them. No warning, no problem, full stock "like out of the box"!

lesbianu said:
If I had extra problems, for sure I would warn you about them. No warning, no problem, full stock "like out of the box"!
Click to expand...
Click to collapse
As per my knowledge, if you flash oxygen OS OTA without magisk then DM verity flag must be triggered, which only goes by sideloading the same OTA file or updated OTA zip file.

No idea, I told you the steps I made few days ago. They worked for me! Want to believe, good. Don't want to believe, even better.
Was on OOS 5.0.4 (bootloader unlocked), decrypted to test Pixel Experience 9.0 for 2 days and then returned to "full stock" OOS 5.0.5 (bootloader locked) to send the phone in service for upper speaker problems. I know it was not necessary to lock the bootloader, but it was my personal choice.
P.S. - Stop quoting the previous post, it's not necessary.

ersandeepkr said:
As per my knowledge, if you flash oxygen OS OTA without magisk then DM verity flag must be triggered, which only goes by sideloading the same OTA file or updated OTA zip file.
Click to expand...
Click to collapse
DM verity is triggered when changes are made to the system/kernel. If you flash a stock OTA file (with no Magisk or other changes) then DM verity is not triggered. Maybe it will be triggered when TWRP is still on the device (not 100% on that), but that will be taken care of when TWRP is overwritten.
You can sideload the OTA as described on the OnePlus website, if you like. But I don't think the result will be any different.

Help getting from LineageOS 14.1 to OxagenOS 5.08 (Something wrong with flash mem?)

Hi,
maybe someone here can help me or point me in the right direction for a guide. That would be much appreciated!
I have a Oneplus 3T (A3003) that I flashed to LineageOS 14.1 with Magisk-Root a while ago.
I have been stuck on 14.1-20171005-NIGHTLY-oneplus3 for a while now, because since then, whenever I tried to do a nandroid backup from within TWRP, the backup failed because of some kind of error on the data partition (I believe). I haven't flashed a new version since then and haven't come around to it until now, because everything ran very smoothly. :silly:
Since I would like to switch to a more modern ROM (I was thinking of going back to Oxygen OS (5.08)) I started playing around with it yesterday and noticed that TWRP (I think 3.2.0) would not start anymore. It will always get stuck on the logo screen.
I then tried to flash a new version (3.2.3.1) through the Official TWRP app. It still got stuck on the logo screen and I tried flashing 3.2.3.0 after reading about problems with 3.2.3.1 but the results were the same.
Can you please tell me how to get TWRP working again and how to flash OxygenOS 5.08 on my 3T or point me to the neccessary guides?
Thank you.
Data about the phone:
ONEPLUS A3003
Android Verson 7.1.2
LineageOS Version 14.1-20171005-NIGHTLY-oneplus3
Security Oct. 5th 2017
Baseband MPSS.TH.2.0.c1.9-00102-M8996FAAANAZM-1.89286.1.99649.1
Kernel 3.18.31-lineageos-g0036392...

As OOS implies enforced encryption of data partition, going to an from it can be a bit tricky. Simplest way is by wiping using Qualcomm factory restore tool and then just OTA upgrade or flash latest OOS zip.
Skickat från min ONEPLUS A3003 via Tapatalk

@r_wraith, I'm thinking that your data may be formatted f2fs and be encrypted but no on-boot password, and have a lot of data in your user data. This could cause a long start time in TWRP.
So try waiingt for about 5 minutes when you boot into TWRP. It may end up getting past the logo screen.
Sent from my OnePlus3T using XDA Labs

BillGoss said:
@r_wraith, I'm thinking that your data may be formatted f2fs and be encrypted but no on-boot password, and have a lot of data in your user data. This could cause a long start time in TWRP.
So try waiingt for about 5 minutes when you boot into TWRP. It may end up getting past the logo screen.
Click to expand...
Click to collapse
That worked, thank you. Yes, my data partition is/was encrypted.

Since TWRP seems to be working again, do I need to flash some kindof firmware upgrade before I flash Oxygen OS or is this included in the OxygenOS-Image and only needed for flashing ANdroid 8 Custom ROMS?

r_wraith said:
Since TWRP seems to be working again, do I need to flash some kindof firmware upgrade before I flash Oxygen OS or is this included in the OxygenOS-Image and only needed for flashing ANdroid 8 Custom ROMS?
Click to expand...
Click to collapse
The OOS zip includes the firmware. Custom ROMs don't because they use the OOS firmware. The firmware is stored in separate partitions so it isn't affected by wiping the system and data positions.
Since you're coming from Los 14.1 you'll need to do the following in TWRP:
- take a backup of your current system
- do a factory reset to clear the data partition without losing the files stored on internal storage
- flash the OOS zip file
- flash Magisk 18.0 which will root the phone as well as prevent TWRP from being replaced by the stock OOS recovery
Sent from my OnePlus3T using XDA Labs

Few questions regarding rooting and flashing.

Hello XDA fam, I just picked up a 3T and unlocked the bootloader.
I was just wondering what the general flashing process was for this
device (A3000). Also a tad confused about this dm-verity ...
disabler zip, is this and format data required every time you flash a
new ROM?

MoistPicklez said:
Hello XDA fam, I just picked up a 3T and unlocked the bootloader.
I was just wondering what the general flashing process was for this
device (A3000). Also a tad confused about this dm-verity ...
disabler zip, is this and format data required every time you flash a
new ROM?
Click to expand...
Click to collapse
Dm-verity warnings are similar to the unlocked bootloader screen you get, but are red. You get them if you are running stock OOS and modify the system partition.
You don't need the dm-verity disabler unless you've got a dm-verity warnings screen.
Note that you cannot disable the unlocked bootloader warning you get every time the phone boots except by re-locking the phone.
Another thing to note: if you are running stock OOS and flash TWRP, then TWRP will be replaced by the stock recovery when your reboot the phone unless you:
- use a patched boot image like the one from @Xennet's thread https://forum.xda-developers.com/oneplus-3t/how-to/dm-verity-disable-oxygen-os-t3922324/post79357241
- use a custom kernel, or
- use Magisk.
Flashing using TWRP is just like any other phone. If you're changing ROMs then you need to do a clean install (wipe /data and/system).
Some ROMs don't handle an encrypted phone (most Android 10 ones except for Los and PE), so you you have to remove the encryption before using those ROMs (TWRP>wipe>format data).
Finally if your phone is unlocked and running OOS 5.x or lower, and you want to upgrade to OOS 9.x then you'll either have to:
- remove the encryption (but can re-encrypt after installing 9.x) or
- use the modded firmware (that keeps the 5.x bootloader and keys) so that you don't have to remove the encryption. See https://forum.xda-developers.com/on...-5-0-8-firmware-barrier-t3941164/post79758055
Sent from my OnePlus3T using XDA Labs

BillGoss said:
Dm-verity warnings are similar to the unlocked bootloader screen you get, but are red. You get them if you are running stock OOS and modify the system partition.
You don't need the dm-verity disabler unless you've got a dm-verity warnings screen.
Note that you cannot disable the unlocked bootloader warning you get every time the phone boots except by re-locking the phone.
Another thing to note: if you are running stock OOS and flash TWRP, then TWRP will be replaced by the stock recovery when your reboot the phone unless you:
- use a patched boot image like the one from @Xennet's thread https://forum.xda-developers.com/oneplus-3t/how-to/dm-verity-disable-oxygen-os-t3922324/post79357241
- use a custom kernel, or
- use Magisk.
Flashing using TWRP is just like any other phone. If you're changing ROMs then you need to do a clean install (wipe /data and/system).
Some ROMs don't handle an encrypted phone (most Android 10 ones except for Los and PE), so you you have to remove the encryption before using those ROMs (TWRP>wipe>format data).
Finally if your phone is unlocked and running OOS 5.x or lower, and you want to upgrade to OOS 9.x then you'll either have to:
- remove the encryption (but can re-encrypt after installing 9.x) or
- use the modded firmware (that keeps the 5.x bootloader and keys) so that you don't have to remove the encryption. See https://forum.xda-developers.com/on...-5-0-8-firmware-barrier-t3941164/post79758055
Click to expand...
Click to collapse
Wow thank you for the detailed info, I really appreciate the insight.
I am currently running the latest OOS update 9.0.6 I believe.
Once I have TWRP installed do I swipe and enable modifications?
Flashing Magisk afterwards avoids the bootloop and allows me to
keep TWRP in place of the stock recovery as you said, correct?
So installing most ROMs seems fairly straightforward, following
the flashing instructions. However if I were to install an Android
10 ROM wouldn't formatting data remove all zips and everything
from the internal storage? So at that point I'd have to copy back
all my ROMs and zips back to the phone in TWRP and flash from
this point correct?
Sorry for the loads of questions, my most recent device was a
Note 9, which has a locked bootloader, so it has been a while since
I have flashed anything or used TWRP.

MoistPicklez said:
Wow thank you for the detailed info, I really appreciate the insight.
I am currently running the latest OOS update 9.0.6 I believe.
Once I have TWRP installed do I swipe and enable modifications?
Flashing Magisk afterwards avoids the bootloop and allows me to
keep TWRP in place of the stock recovery as you said, correct?
Click to expand...
Click to collapse
You don't need you enable modifications of the system partition. Any zip you flash will make the system writable if required.
So, just flash Magisk.
MoistPicklez said:
So installing most ROMs seems fairly straightforward, following the flashing instructions. However if I were to install an Android
10 ROM wouldn't formatting data remove all zips and everything from the internal storage? So at that point I'd have to copy back all my ROMs and zips back to the phone in TWRP and flash from this point correct?
Click to expand...
Click to collapse
Correct. So it's best to take a backup of your current system and backing up everything on internal storage (/sdcard) to an external drive or PC.
The fastest way to take the backup is to use ADB.
Code:
adb pull /sdcard
MoistPicklez said:
Sorry for the loads of questions, my most recent device was a
Note 9, which has a locked bootloader, so it has been a while since
I have flashed anything or used TWRP.
Click to expand...
Click to collapse
You'll find that nearly all the rom, kernel, and recovery development threads are under the OnePlus 3 forum in https://forum.xda-developers.com/oneplus-3/oneplus-3--3t-cross-device-development as they are unified: good to flash on both the 3 and 3T.
Sent from my OnePlus3T using XDA Labs

BillGoss said:
You don't need you enable modifications of the system partition. Any zip you flash will make the system writable if required.
So, just flash Magisk.
Correct. So it's best to take a backup of your current system and backing up everything on internal storage (/sdcard) to an external drive or PC.
The fastest way to take the backup is to use ADB.
You'll find that nearly all the rom, kernel, and recovery development threads are under the OnePlus 3 forum in https://forum.xda-developers.com/oneplus-3/oneplus-3--3t-cross-device-development as they are unified: good to flash on both the 3 and 3T.
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Awesome info, big thanks to you my good sir. Finally
on Havoc 2.9 and decrypted. Now just gotta get a feel
for this phone and keep on reading. Cheers!