How I installed F-Droid Privileged Extension on Rooted Android 8.1

[amondo]

Introduction
F-Droid has an extension called the F-Droid Privileged Extension, which can be convenient because it allows F-Droid to install updates in the background.

I tried installing it using the Gemini's standard Recovery, but the zip failed to install due to "Signature verification failed". So I re-partitioned and then re-flashed my Gemini with TWRP, and after a lot of trial and error, I got it working in the end.

Pre-requisites
- You have Rooted Android on Boot 1 and TWRP Recovery on Boot 2
- You know how to use adb in Android SDK

Limitations
- Only tested using the Android 8.1 Gemini firmware

Steps
1. Install F-Droid on the Gemini.
2. On the computer, download the F-Droid Privileged Extension "OTA" zip file from https://f-droid.org/en/packages/org.fdroid.fdroid.privileged.ota. Find the latest version and click Download Zip.
3. Reboot the Gemini into TWRP by holding down right side button.
4. In TWRP, Swipe to Allow Modifications.
5. Go into Mount menu and check the box next to System (do not forget this step!!), then press back to return to main menu.
6. Go into Advanced menu, then ADB Sideload, then Swipe to Start Sideload.
7. On the computer, sideload the zip file using adb, for example: adb sideload org.fdroid.fdroid.privileged.ota_2130.zip. After successful install, just reboot as normal.

I don't remember if I also had to install the non-zip variant of the privileged extension within F-Droid itself, or whether F-Droid did this automatically. But you should install it anyway as it provides updates and it means you don't have to re-install through TWRP again.