RR Remix for OnePlus 3T Updater process ended with ERROR: 7

While trying to update my OnePlus 3T with Custom ROM Resurrection Remix I received an error in TWRP.

Updater process ended with ERROR: 7
Error installing zip file '/data/media/0/TWRP/RR-N-v5.8.1-20170213-oneplus3t-Official.zip'
Comparing TZ version TZ.BF.4.0.1-83199 to TZ.BF.4.0.1-76917
assert failed: oppo.verify_trustzone("TZ.BF.4.0.1-83199") == "1"

Link to ROM [Official][OMS] Resurrection Remix [OP3T][Rom&Kernel][Feb 13]

I am not sure, if the error was caused by a version jump by me or it was caused by trying to get the Stock Camera from OxygenOS.

If you get the same error after trying this for stock cam, you'll be fine, don't worry. I fixed it directly on the phone using MiXplorer with root.

Open your ZIP File and go to /META-INF/com/google/android
open updater-script as Textfile
delete the line assert(oppo.verify_trustzone("TZ.BF.4.0.1-83199") == "1");

after that, TWRP hat no more problems, the ZIP file just installed fine.

update: found out, error was caused by me. didn't checkt post 2 in official forum post, had to update firmware file as well