Would like to know this as well, I rooted my oneplus recently, and the moment the secure boot chain of trust broke, no security sensitive apps worked.
I've signed my own secure boot loader on Linux, but I don't know if you can do it on Android at all, since you don't have keys or can modify the secure storage easily.
I've signed my own secure boot loader on Linux, but I don't know if you can do it on Android at all, since you don't have keys or can modify the secure storage easily.