[Android Software/Hacking General [Developers Only]] physwizz:
These instructions are clear

Installing Custom Recoveries

A. Preparation.

1. Download firmware for your device

2. Extract ap file using Zarchiver

3. Patch the ap file with a magisk which will patch both boot.img and vbmeta.img (from magisk, choose install then select file to patch)

Exynos 850 Resources

t.me

note: if you don't want root then just extract the vbmeta.img and use zarchiver to add it to my twrp.tar file.

You can flash this new file from odin at step 5

For Exynos 850 android 11 use a21s patched magisk.

For Exynos 850 android 12 and most other devices use delta magisk

4. Unlock OEM in developer options

5. Attach phone to pc and reboot to download mode

6. flash patched ap file.

Or..

Extract boot.img and vbmeta.img and add them to the TWRP zip.

7. Download recovery.img or download twrp.tar and extract recovery.img using Zarchiver.

B.Installation

Method 1.

1. Connect to pc and boot into stock recovery

2. Factory reset

3. Reboot into download mode.

4. flash twrp.tar into the ap slot

5. reboot to recovery from main menu (nor just reboot)

6. Advanced, terminal. Type multidisabler (twice).

7.

Or flash samsung multidisabler zip

Or, for older phones flash dmverity zip

8. Reboot to recovery from main menu (not just reboot)

Backup boot, data, super and dtbo

9. Reboot to system

Method 2.

If you have already installed recovery and decrypted.

1. Boot to recovery.

2. Install recovery.img

3. Choose recovery partition

4. Reboot to system then reboot to recovery

Backup boot, data, super and dtbo

(For Pitch-black just install the zip)

Method 3.

1. Install TWRP app

2. Install TWRP

3. Choose file to flash.(don't select device)

4. Select recovery.img.

5. Reboot to recovery.

6. (You may need to change data partition to ext4 first if format ruins your system)

7. Reboot to recovery.

8. Wipe, format data, type YES.

9. Advanced, terminal.

10.Type multidisabler (twice).

Or flash samsung multidisabler zip

Or, for older phones flash dmverity zip

11.Reboot to recovery

12. Flash Magisk for root(only for method 3)

13. Backup boot, data, super and dtbo

Method 4

Using a second phone

Physwizz Collection

To flash TWRP from phone1 to phone2 Only if you have already installed recovery and decrypted. Method 1 Thor https://t.me/fdur2021projects/314 Method 2 heimdall 1. Install this termux on phone1 2. Setup storage termux-setup-storage 3. Install this Heimdall Magisk module on phone1 Or...

t.me

C. Recovery Problems

Most recovery issues can be solved by attending to the following issues.

1. Did you root using the full ap file patched Magisk .

(This contains the patched boot.img and vbmeta.img)

Exynos 850 users must use the special a217 magisk?

2. Did you then go all the way through the setup process?

3. Did you download the recovery to match your baseband?

See https://t.me/a127f_res/54 for Exynos 850 recoveries

4. Did you hold down power and volume up after Odin says pass?

5. Did you format data from stock recovery?

6. Did you type multidisabler twice?

7. Did you reboot to recovery by choosing reboot from the menu and then choosing recovery?

8. To avoid touch issues go to settings and untick "allow time out"

D.To restore Stock Recovery

1. Attach phone to pc and reboot to download mode

2. flash patched ap file.

3. reboot

Or just flash stock recovery.img from twrp and reboot.

@physwizz