For Android 11/12 GSIs where the above fails, the DTBO (Device Tree Blob Overlay) needs patching.
Huawei’s EMUI is a heavily customized Android skin. Its closed-source components make it much harder to build clean AOSP-based custom ROMs compared to devices from manufacturers like Xiaomi or OnePlus.
He rebooted.
Experience Android 10 or 11 (LineageOS 17.1 / 18.1) layouts.
(tap Build Number 7 times).
The Y5 2019 launched with Android 9, a version that supports Project Treble. This means, in theory, you could flash a GSI of Android 10, 11, or even later versions. The primary challenge remains unlocking the bootloader, but for those who achieve it, GSIs represent the only viable “custom ROM” path.
Install (root required).
Tap (in the bottom right corner) because GSIs download as .img files, not .zip files. Select your downloaded GSI ROM image.