yashsingh1/xdaforums huggingface dataset:
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Shponglized:
Will do.

Just so we're on the same page, My method will be to ...

reboot into twrp>

backup Boot, Data, and System Image>

Reboot Recovery just for fun>

wipe system>

Restore System_Image
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
No need to wipe system.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Shponglized:
You're right. restoring wipes it automatically doesn't it?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
Absolutely.

I think that we have discovered rule #1: DO NOT WIPE BEFORE RESTORE
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Shponglized:
Wouldn't that wipe just be redundant? It seems weird that it would cause problems.

By the way, I was successful in restoring via System_Image.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
I'm suspicious of the manual wipe; I don't know why.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ozzmanj1:
Finally took the TWRP plunge, but am bootlooping. To 9.0.5 international. I followed the steps:

boot twrp

flash installer (both slots)

reboot recovery

magisk

Bootloops after that, I even wiped cache and still bootloops. Any ideas?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
Which twrp? Can you provide the name?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ozzmanj1:
From this same thread but post 299

https://xdaforums.com/showpost.php?p=78267079&postcount=299
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
Please use the one from OP
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ozzmanj1:
I am using the Tmo variant. Other Tmo users have used this same process without issues. Everything flashes correctly, just bootloops
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
OK
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ozzmanj1:
Can someone provide any light as to what I can do, I followed all the steps, read up before starting the process.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
Very sorry I cannot provide any assistance
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] seetru:
from your pc fastboot boot twrp.img and flash magisk, you have to flash magisk before rebooting
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ozzmanj1:
Yes, I did that. As stated I followed all the steps to a T, from post 299:

https://xdaforums.com/showpost.php?p=78267079&postcount=299

I read further on that some users had to wipe cache and that resolved the issue, but nothing for me... just bootloops
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Shponglized:
I would suggest fastboot flashing stock 9.0.6 and working from there.

And using the recovery and instructions from the OP not from a random post in the 60ish page thread.

Granted those files were from a moderator, but the recovery has been through many iterations in it's short time.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ozzmanj1:
I will start there, thank you

---------- Post added at 03:03 AM ---------- Previous post was at 03:00 AM ----------

Forgot to mention, I am on the Tmo variant, will the instructions on the OP work for my device? I have tried to read up as much as I can, but its been a couple days since last time i was able to stay current.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] seetru:
successful backup and restore

backed up boot, system_image, and vendor_image together - rebooted to recovery and backed up data separately since most problems were happening there - all restored fine and system rebooted without issue
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] tech_head:
Have you flashed it to the 9.06 Unlocked ROM? See other threads.

If not, do not do this.

The boot image will be incorrect and you might brick your phone.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] twinnfamous:
Did the process look like this? I restored all of them together after I wiped system
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] tech_head:
This is what I did.

fastboot flash boot_a "boot image from 9.06"

fastboot flash boot_b "boot image from 9.06"

fastboot boot twrp-fajita-3.2.3-6.img

From inside twrp after entering in my password/pin for working decryption (YEAH!!!!)

install zip -> twrp-fajita-3.2.3-6-installer.zip

install zip -> ElementalX and Magisk 17.3

wipe cache

Boot System and profit!!! :D

Flawless
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] seetru:
yes I also skipped digest check if it matters
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Shponglized:
Everything should work the same between the unlocked version and the t mobile version as far as I'm aware.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] seetru:
red over black themed twrp /w oneplus logo

let the hunt begin :good:
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ozzmanj1:
Okay, I have followed the steps in the first post, same results every time. Everything is successfull, but bootloops. I have now done this 4 times with same end result.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Shponglized:
Check post #637

What he did may work for you.

Otherwise you should probably flash the full stock rom via fastboot.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] seetru:
boot twrp

flassh installer

flash magisk

reboot

don't reboot between flashing installer and magisk
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ozzmanj1:
I have already stated tha exact same steps, that I did. Never got it to boot. Finally had to flash full 9.0.6 and wipe all my data...and start from scratch
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] seetru:
ok look at the steps you originally posted, you must install magisk after twrp installer first - twrp will not load if boot image is not rooted and system won't either

I don't want you to bootloop again so:

boot twrp

flash twrp installer

flash magisk

reboot system

then boot recovery and you should be fine - good luck
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] geminium:
Could anyone suggest how to get back double tap to wake feature on the stock kernel. I went back to stock kernel from Elemental and it's still same no dt2w....
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] seetru:
go back and look at the title of the post
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] H4X0R46:
Alright so the last build fixed system formatting. Is it working for everyone? I haven't tried it, no roms out and I probably won't flash anything drastic until there is roms for this device. But thought I'd check to see if anyone is still having the issue.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] liver20:
I can restore data 100%

Enviado desde mi ONEPLUS A6013 mediante Tapatalk
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] SpectraFun:
Also no problem on restore system, data and boot.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] felek73:
It will be my second attempt to go through backup/ restore procedure. First attempt made me to unbrick my phone :)

What is the right procedure? Which items should be choosen on backup/ restore screen? Should I wipe/mount something manually?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] kjcsg:
Is anyone else having issues with the phone only booting to recovery or bootloader? I am unable to boot to system after going from twrp 3.2.3-1 to twrp 3.2.3-6. It boots straight to recovery unless I specify to boot to bootloader. Not sure what to do here.

EDIT----

Turns out the problem was magisk. After I re-ran the magisk 17.3 installer zip on twrp 3.2.3-6 the phone booted perfectly fine. It took a little while at the unlocked bootloader screen, but it got past it and booted just fine. Just in case anyone else is having issues with recovery boot loop.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] mauronofrio:
You need to flash magisk again.

It's already written in the first post.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] kjcsg:
Yea I stupidly overlooked that when I got the to the stock part, thinking it didn't apply to me since I was already rooted and all. My bad. Thank you though!
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] tuxing:
Just flashed 3.2.3-6, now see 3.2.3-7

What are the changes?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] MelvinGt5:
Cuestion:

1.Install OEM Firm.

2.Unlock Bootloader:

3.Flash TWRP.

4.Flash TWRP installer.

5.Reboot TWRP.

6. Flash Magisk.

7.Flash Stock Boot 9.0.6.

Is that way?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] mauronofrio:
Not a problem :good:

New Fajita TWRP 3.2.3-7

Added the new notch theme ( Image in the thumbnails)

IMG: https://www.androidfilehost.com/?fid=11410963190603862856

Installer: https://www.androidfilehost.com/?fid=11410963190603862857

If you flash stock boot 9.0.6 you will overwrite twrp and magisk...
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Araa01:
Easy way to instal this twrp is your program yes? Unlock bl and click flash twrp and finish? Oxygen 9.0.6

Wysłane z mojego ONEPLUS A6013 przy użyciu Tapatalka
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] MelvinGt5:
Ok. In step 6 Reboot the Device and is ready to use?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] SpectraFun:
Vibration not work in TWRP.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] mauronofrio:
Added the new notch theme

Yes, you can use the tool, but you need also to root your phone or it will not boot. So unlock bootloader and from the tool you should use "Recovery Flasher and Root" option, choose the twrp, check "Root after flash" , click on flash, choose magisk 17.3 and click on continue, the tool will automatically download and flash needed files

Yes, unfortunately it is not working and i don't know why.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Araa01:
Your program is the best! Thx bro good job! :)

Wysłane z mojego ONEPLUS A6013 przy użyciu Tapatalka
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] mauronofrio:
Maybe because you have not enabled debug usb?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] 5upon:
One minor cosmetic issue with 3.2.3.-7 - the line of text above the encryption password entry field is cut off. Only the top (or bottom?) few pixels are visible. Unlocked 6T, blu_spark 58, Magisk.

Thanks for all your work on this!
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] mauronofrio:
Yes maybe there is a little bug on the new theme, can you please make a picture of it? Screenshot or photo is the same, just o understand it.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] 5upon:
Photo attached. It looks like the static text is being overwritten by the form field.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] VampireHeart:
Good to know. :svetius:
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] jl2222:
I have always manually wiped before a restore system as well. I was unaware TWRP does a wipe of system automatically before restoring system partition. Does TWRP automatically wipe the other partitions as well such as Data during the restore process or is it still necessary to manually wipe data and cache before a full restore?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] mauronofrio:
Check the new 3.2.3-8 build I should fix it
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] suzook:
We went from no flashing activity, to overload!!!! LOL. Thanks for all you do.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ledvedder:
Ok, I backed up Boot, Data, System, and Vendor. I'm trying to restore Boot, System, and Vendor but received the 255 error when trying to restore System. Anything I can do to resolve this?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
Did you backup system or system image?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ledvedder:
System. Now the phone will only boot into bootloader.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
I was told to back up the image. I don't know if that makes a difference
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ledvedder:
Great! I guess I have a brick now.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] pyry666:
Verified.

3.2.3-8 fixed previous text cut off.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] mauronofrio:
Naaa, just flash stock rom from twrp or fastboot
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
https://xdaforums.com/oneplus-6t/how-to/rom-stock-fastboot-roms-oneplus-6t-t3862516
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ledvedder:
How do I get into either twrp or fastboot?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
Or try this one if you have the international version (there's one for tmo version too)

https://xdaforums.com/oneplus-6t/how-to/tool-6t-msmdownloadtool-v4-0-oos-9-0-5-t3867448

---------- Post added at 09:11 PM ---------- Previous post was at 09:06 PM ----------

Fastboot from power off: press and hold down volume up and down while pressing the power button
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ledvedder:
What's weird is that my phone is at the bootloader screen, where you can select power off, restart bootloader, recovery mode, etc, but "adb devices" from my pc shows no devices. This has always worked. Previously, I installed the international 9.0.6 rom, rooted, etc. I'm on T-Mobile.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
Adb won't work in bootloader

Fastboot devices to see your phone
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ledvedder:
I knew that! Haha! Thanks, that worked.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lostunsunghero:
Settings>display>ambient display>tap to wake

If you haven't already figured it out.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Nsane457:
I haven't yet been able to successfully restore from a nandroid backup. Made a backup of all partitions, including system_image and vendor_image but excluding system and vendor. Restored all partitions that were backed up. Reflashed magisk. After rebooting, it reboots again into TWRP. I had to, once again, fastboot install stock images to get the phone to boot.

What am I doing wrong?

EDIT: The last time was with twrp-fajita-3.2.3-6.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] zakkyzombie:
I don't know Wich version I installed when I first got it a week ago, but I went to update via flashify and it can't find my recovery partition. So I got the zip and went to flash it and my sdcard is nothing but folders like 67gjeh638;ysjD8. Why are my folders like this? Luckily I didn't find it, because I was unaware of the no magisk flash no boot. Wich brings me to my next question, what version of magisk do we use? I have 17.3 installed from the tool, but I don't see any modules for it. Can we use 17.1? Where can I find the zip for it?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Nsane457:
I just flashed twrp-fajita-3.2.3-8 and did a backup of boot, data, system_image, and vendor_image partitions. I then immediately restored them, rebooted and it booted back to TWRP but with decryption not working.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ledvedder:
I guess I won't be testing a restore yet.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] dipole:
Can't see anything you did wrong here, I was going to test a restore tonight but will hold off, seems it's broken.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Nsane457:
The relevant section of recovery.log after restore and reboot:

I:File Based Encryption is present
e4crypt_initialize_global_de
calling retrieveAndInstallKey
Key exists, using: /data/unencrypted/key
Using Keymaster HAL: 4 from QTI for encryption. Security level: TRUSTED_ENVIRONMENT, HAL: android.hardware.keymaster@4.0::IKeymasterDevice/default
Added key 485204562 (ext4:7565334f746141f0) to keyring 15610059 in process 540
Added key 1053836697 (f2fs:7565334f746141f0) to keyring 15610059 in process 540
Added key 262110947 (fscrypt:7565334f746141f0) to keyring 15610059 in process 540
contents mode 'ice' filenames 'aes-256-cts'
Wrote system DE key reference to:/data/unencrypted/ref
e4crypt_init_user0
Preparing: /data/misc/vold/user_keys
Preparing: /data/misc/vold/user_keys/ce
Preparing: /data/misc/vold/user_keys/de
Skipping non-de-key ..
Using Keymaster HAL: 4 from QTI for encryption. Security level: TRUSTED_ENVIRONMENT, HAL: android.hardware.keymaster@4.0::IKeymasterDevice/default
Added key 920572429 (ext4:e16fa67629e09e49) to keyring 15610059 in process 540
Added key 316852906 (f2fs:e16fa67629e09e49) to keyring 15610059 in process 540
Added key 285130339 (fscrypt:e16fa67629e09e49) to keyring 15610059 in process 540
Installed de key for user 0
Skipping non-de-key .
e4crypt_prepare_user_storage for volume null, user 0, serial 0, flags 1
Preparing: /data/system/users/0
Preparing: /data/misc/profiles/cur/0
Preparing: /data/system_de/0
Preparing: /data/misc_de/0
Preparing: /data/vendor_de/0
Preparing: /data/user_de/0
contents mode 'ice' filenames 'aes-256-cts'
Failed to prepare user 0 storage
e4crypt_init_user0 returned fail
e4crypt_initialize_global_de
Already initialized
e4crypt_init_user0
Preparing: /data/misc/vold/user_keys
Preparing: /data/misc/vold/user_keys/ce
Preparing: /data/misc/vold/user_keys/de
Skipping non-de-key ..
Skipping non-de-key .
e4crypt_prepare_user_storage for volume null, user 0, serial 0, flags 1
Preparing: /data/system/users/0
Preparing: /data/misc/profiles/cur/0
Preparing: /data/system_de/0
Preparing: /data/misc_de/0
Preparing: /data/vendor_de/0
Preparing: /data/user_de/0
contents mode 'ice' filenames 'aes-256-cts'
Failed to prepare user 0 storage
e4crypt_init_user0 returned fail
e4crypt_initialize_global_de
Already initialized
e4crypt_init_user0
Preparing: /data/misc/vold/user_keys
Preparing: /data/misc/vold/user_keys/ce
Preparing: /data/misc/vold/user_keys/de
Skipping non-de-key ..
Skipping non-de-key .
e4crypt_prepare_user_storage for volume null, user 0, serial 0, flags 1
Preparing: /data/system/users/0
Preparing: /data/misc/profiles/cur/0
Preparing: /data/system_de/0
Preparing: /data/misc_de/0
Preparing: /data/vendor_de/0
Preparing: /data/user_de/0
contents mode 'ice' filenames 'aes-256-cts'
Failed to prepare user 0 storage
e4crypt_init_user0 returned fail
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] lollyjay:
Thanks for the log
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] H4X0R46:
Alright, got caught up in the thread. Thanks for the new build! I'm glad you guys were able to get a working TWRP even before Dees_Troy did!
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] ledvedder:
Has anyone performed a successful backup and restore? If so, what were your steps? Also, which carrier and rom were you running?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] stryver:
Did you try switching slots?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Giansi:
To update from 3236 to 3238 build is just needed to flash 3238 installer in TWRP then magisk right?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] micky387:
which ROM do you install for GAPPS?

otherwise, I suspect busybox. it's deprecated for our device / platform. We use system as root and busybox dont know that. We should normally switch to toolbox..

I will try but I am afraid for decrypt ...
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] mauronofrio:
You have multi user when you did a backup?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Nsane457:
No.

I tried to install lineageos. mindthegapps failed so I erased system, data, cache, and tried again with opengapps. lineageos rom seems to succeed while every gapp installer fails.

No.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] micky387:
ok lineageos for op6 ?

when i was developing lineageos for mate9, i still had this error with mindthegapps

switch to opengapps and try again
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] foobar66:
EDIT: I restored backup for system, vendor, boot ... backup was OK but restore did not work. Reboots now into twrp.

**** ... I thought the restore changed the boot partition from A to B. So I changed it back to A.

Now my device only boots into the bootloader and when I do: fastboot boot twrp-fajita-3.2.3-8.img thenI get:

downloading 'boot.img'...
OKAY [ 0.787s]
booting...
FAILED (remote: Failed to load/authenticate boot image: Load Error)
finished. total time: 0.804s

How do I get out of this?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] headcreepz:
I just flashed the 9.0.6 update fastboot
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] foobar66:
Can you please give a bit more detail ... how? What file?

I do have a raw dump of ALL original partitions on my PC ...
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] felek73:
Was in the same boat two days ago..you have to use this and start clean..

https://xdaforums.com/oneplus-6t/how-to/tool-6t-msmdownloadtool-v4-0-oos-9-0-5-t3867448

I lost all data and afraid doing any restore
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] SpectraFun:
Nice we have a good working twrp but no rom for flashing.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] foobar66:
Thanks a lot ... starting to recover ... I'm back into twrp ...

EDIT: fully recovered ;)
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Unghiutza:
Quick question, i'm on 3.2.3-6, how can i upgrade to -8 without any problems? Do I just flash the installer or do i have again to boot into the .img and then flash the installer?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Araa01:
Pls read topic broo. :(

Wysłane z mojego ONEPLUS A6013 przy użyciu Tapatalka
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] KOLIOSIS:
Put the .3.2.3-8 installer.zip & Magisk 17.3.zip & on your phone's file system/directory

1) Boot the 3.2.3-8.img in fastboot: fastboot boot fajita-twrp-3.2.3-8.img

2) Once TWRP 3.2.3-8 is booted,flash the 3.2.3-8 installer.zip,then,flash Magisk 17.3 .zip

Then,reboot your phone & you should be good to go.

Install the Magisk Manager .apk if desired.
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] Unghiutza:
I'm already rooted with magisk and have 3.2.3-6 twrp installed. I'm asking this for update. Just to update I have to redo all the steps? Or is it enough to just flash the new twrp?
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] KOLIOSIS:
See the original post.

https://xdaforums.com/oneplus-6t/development/recovery-unofficial-twrp-touch-recovery-t3861482

It gives the steps for new install & updating.

Install guide:

1. Install fastboot tools from google's sdk on your PC

2. Enter fastboot mode

3. Unlock your bootloader

4. Run "fastboot boot recoveryimgfilename.img" in command line (if you want to have it permanently you should flash the installer)

5. If you will flash the installer and you are stock you need also to flash magisk or your phone will not boot again

Tips:

If you already have a twrp flashed you can only flash the new installer zip to update your TWRP (remember to flash again magisk or your system will not boot).
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] dipole:
no, just go into TWRP and install the update. Make sure to also install magisk before you reboot
[OnePlus 6T  ROMs, Kernels, Recoveries, & Other Dev] suzook:
I was in same boat 3 times, and there is definitely some issue still. I DON'T have a multi user account, and don't have parallel apps, and can NEVER restore my data. I'm not sure why some people can, and apparently some cannot.