root な端末だと拾えるな
これ端末戻すと token 変わるから使えなくなるよな……

$ adb shell
1|shell@MK16i:/ $ su
root@MK16i:/ # ls -l /data/data/com.valvesoftware.android.steam.community/files/
-rw-rw---- u0_a59 u0_a59 448 2018-08-31 22:25 Steamguard-76561198085918260
$ adb root
$ adb pull /data/data/com.valvesoftware.android.steam.community/files/Steamguard-76561198085918260
$ file Steamguard-76561198085918260
Steamguard-76561198085918260: ASCII text, with very long lines, with no line terminators
$ lv Steamguard-76561198085918260
$ jq .uri Steamguard-76561198085918260 | sed -e 's/^.*=\(.*\)&.*$/\1/'
OXYBZQLEOB7KKFAPERMN8EGNOLJWEDYZ

"KeeTrayTOTP/README.md at master · victor-rds/KeeTrayTOTP · GitHub" https://github.com/victor-rds/KeeTrayTOTP/blob/master/README.md#steam-totp-secret https://gnusocial.matoken.org/attachment/144126