During the initial splash screen boot sequence, look for a warning message that states: "The bootloader is unlocked and software integrity cannot be guaranteed." This is the definitive visual indicator of success.
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The current installed on your device
Are you running into a in the command prompt?
This is the ultimate goal for most who go through this hassle. A custom recovery like TWRP (Team Win Recovery Project) allows you to flash custom ROMs (like LineageOS, Pixel Experience, etc.). This is the only way to get a modern version of Android (e.g., Android 13 or 14) on your Aquos Zero 2 once Sharp stops support.
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