There are a few known bugs with this release:

DT2W only works on some display panelsSome issues with the Mi A2 Camera app (“Could not connect to Camera” crashes often)SELinux is permissive

But everything else should be working perfectly fine, and if not, it is more than likely a vendor issue and you should contact your ROM dev. You can restore your apps via Google Backup or Titanium Backup if you engage those options before beginning to follow this guide.

Requirements / Downloads:

TWRP Fastboot only with Tissot Manager (Required)CosmicDan’s TWRP Installer (Required)ResurrectionRemix Oreo Vendor.img (Required)A/B system Pie PR2 img (Required)POST-sGSI 1 tissot zip (Required)POST-sGSI 2 tissot zip (Required)A Treble-compatible kernel (Moun, ProjectK, Velocity) (Required)Magisk 17.1 (Optional)Data Transfer Tool APK (Optional, Recommended)Nav Bar Enable (Magisk module) (Optional, Recommended)

Once you’re inside the Android System, you need to install the latest Google Play services, either as manual APK installation or via ADB flash. This will fix the Pixel Setup and Google Backup issues, and you can also access the Play Store without further issue. If you want root via Magisk, you can install Magisk 17.1, which is Treble-compatible. You should install the Data Transfer Tool APK as well. At this point, there are a couple tweaks to do to fix some things. First, to enable USB MTP, you should go into Developer Options and change the File Transfer option to USB MTP.

Enable the Navbar

To enable the nav bar, you need to install the Nav Bar Enabler via Magisk. Reboot your Xiaomi Mi A1, then Settings > System > Gesture and enable Swipe Up on Home Button to enable the Nav Bar Gestures.

Installing Substratum

If you install this Substratum APK from the Telegram channel, it has much better support for Android Pie. After building the themes, you need to reboot, then go into Manager and enable the overlays for the theme you have built.

Updating from PR1 to PR2

You don’t need to wipe data to update from PR1 to PR2. You just need to wipe SYSTEM, then flash PIE PR2 AB GSI, and reboot to system. For updating your post GSI zips, you need to wipe VENDOR, flash the vendor, then flash the POST zips and reboot to system.

OK Google

Install the latest Google App update from the Play Store. Download the April or July modem patch and flash via TWRP. See which one makes OK Google work for you.

Camera

Library of GCam mods (not all of them will work, depends on the device): https://www.celsoazevedo.com/files/android/google-camera/

Recommended: https://temp4-f.celsoazevedo.com/file/gcamera/GoogleCamera-Pixel2Mod-Arnova8G2-V8.2.apkIf you want dual camera support, use CStark Tele: https://temp4-f.celsoazevedo.com/file/gcamera/cstark27_GCam_5.1.018_24_tele_v0.1a.apk

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