October is here, and that comes with another update! We’ll be using TWRP and the factory images to update our rooted Pixel to the October Security Update.
TWRP (3.3.1-0) can decrypt
/data successfully on Android 10, but that is only offered as a bootable TWRP image. The latest installer .zip is still based on 3.3.0-0. This means the image you first boot will be able to decrypt the
/data partition (so you can see the contents of your internal storage). But once you flash the TWRP installer and reboot back into the recovery, you’ll be using TWRP 3.3.0-0.
TWRP 3.3.0-0 provides a way to install a recovery image to the ramdisk, so you can install the TWRP 3.3.1-0 image via TWRP.
Therefore in this case, you can flash TWRP Installer & Magisk while booted from the TWRP 3.3.1-0 image.
TWRP (3.3.0-0) cannot mount the
/data partition while it is encrypted. You can attempt to remove your screen lock before booting TWRP. But I would recommend sideloading Magisk in TWRP via ADB Sideload so you don’t have to re-enroll your fingerprints and reconfigure your apps.
Sideloading in TWRP
From TWRP’s main menu, go to Advanced > ADB Sideload > Swipe to start Sideload.
Then use the ADB command:
adb sideload [zip you wish to sideload & flash]
We can use the latest stable version of Magisk (v20.0) which has been updated to support Android 10 on almost all devices. Luckily that includes the Pixel and Pixel XL.