UPDATE: I have since updated to official 5.1.6 via OTA flashed TWRP and Magisk. The backup finished successfully with no sign of 255 error and once rebooted the USER ID and all 999 folders were still gone after the update and switched slots.
And I present to you....... The OnePlus 6 Xray notch background. Matches button and camera placement.
For anyone who is interested in having a custom TWRP theme I have good news for you. This has been tested on TWRP 3.2.1 and Oxygen 5.1.6. Pictures attached.
Obviously you must be rooted but for those who have no idea these are the requirements. ...
Look what I just found by checking for an update..... Used vpn to Canada
Yes it's official 5.1.7 is live
Just wondering if twrp and Magisk will still work?