DirtySanta + TWRP 3.3 + LineageOS 17.1 = Static Boot. No ADB. Death :(

[netspider1]

Hello guys, please help,
brand new LG V20 H990DS out of the box, walk the way to get LineageOS 17.1 just to have a short gimps and happiness, and deterioration started.
To end up with Static screen on boot, on Download mode, and on TWRP recovery, no ADB, no fastboot. Only COM PORT detectable :crying:

Brand new V20 H990DS with Android 8, I did:
on Version before Dec 2016, Singapore H990DS 10d I did

LGUP pathed for features, did FULLDUMP. Flashed old version before Dec 2016

[ROOT] DirtySanta comes for the H990 https://forum.xda-developers.com/v20/development/dirtysanta-h990-t3624296
Keep the aboot and boot backups

Set correct country code to the NETCODE in the service menu *#546368#*990# -> SVC Menu -> Version Info -> NT Code

I put recovery TWRP-3.0.2. Rooted with Magisk.
The stock Download mode (Hold Vol+ and connect to PC while it was powered off) turn into Static boot. I guess because aboot->laf chain got replaced by DirtySanta.
So no more Stock Download mode anymore

Updated the all firmwares, to the last 10x version (last Android 7) using KDZWriter

Then it turns out LineageOS 17.1 cannot be installed with TWRP-3.0.2 because unable to detect the phone corectly:

E3004: This package is for device: H990, us996, elsa:
this device is .

So Installed the last recovery TWRP-3.3.1 for h990. This was bad decision, did not aware 3.3.1 is full with problems and other people complained. I should try with TWRP-3.2.3 or TWRP-3.2.1.

So I installed LineageOS 17.1 + Gapps with new TWRP-3.3.1. I enjoyed 1 hour on LOS

Decided to make backup and restore with TWRP-3.3.1 and problems started...

failed to mount /system (invalid argument)

applied the solution every time: "Change File System” -> Ext2 (or exFAT ) and then ext4 . The trick was working temporary. I was not able to have reliable backup->restore with TWRP-3.3.1 on my LineageOS.

I returned the old TWRP-3.0.2, reformat&convert the \system partition and deployed the old Android 7 nandroid. All good I saved my phone.
Then I put again TWRP-3.3.1 and try to flash LineageOS backup, but was unable to finish because error

failed to mount /system (invalid argument)

Then decided to flash the good old Android 7 nandroid backup with the new TWRP-3.3.1 but again I couldn't because

failed to mount /system (invalid argument)

Before to deploy the backup I wiped all partitions, including boot, recovery, firmware, and tried to reformat the \system in order to do full restore
in that moment the TWRP stuck on formatting the \system. Screen freeze...
Removed the battery and when get back in TWRP the screen was on half TWRP on half Static boot. So TWRP damaged. No recovery

Cannot connect with ADB

adb devices
List of devices attached
LGUS996d4fa822a recovery

Even device was incorrectly discovered US996. I guess because TWRP 3.3.1, although I downloaded TWRP 3.3.1 for H990

I cant reboot in fast boot

adb reboot bootloader

and no fastboot devices any more, cannot install the recovery again.

fastboot devices

When I was installing recovery every time I was waiting 1 minute and 2 installs. My recoveries was booting every time. Now is damaged coz the mess with partitions inside TWRP 3.3.1 when reformatting them...

Then I tried this, with LGFlashTool pushing on COMPORT 41 the .dz firmware
[Guide] LG V20 Back to Life [Download mode] https://forum.xda-developers.com/v20/how-to/guide-lg-v20-to-life-t3827732
But without stock Download Mode chances was not good. I couldn flash anything.
Even worse, now even I cant see the phone even in recovery with

adb devices

I have static screen on boot, on recovery, and on Download mode.
I still can see the phone only on COM PORT attached every time when I plug the cable and try to get into anything

What I can do in this situation? My story started so well, but I finish worst endup ever

 

[cnjax]

Buy a new phone

Sent from my LG-H910 using XDA Labs

 

[netspider1]

Buy a new phone

Sent from my LG-H910 using XDA Labs

Did it already I have it, will start again This time will avoid the mistake
So before to flash the backup don't wipe anything. Flash the backup, and if it's successful, then wipe and flash again.
I was hurry, still experimenting with unstable recovery, I wipe everything and turns out the backup and TWRP 3.3 is very messy and cannot be flashed, and I fall in dead lock.
Lesson learned. Hope my story is useful to someone to not fall in same situation