https://twitter.com/balika011/status/1107748638095220738?s=19
Triszka Balázs says:
"There is more to the story, and this is gonna be EPIC! They store the root key in plaintext, but they are not using it. On 7.0+ they set the tsec_root_keys + 0x10 then don't even touch it. It's a leftover. What...