HOW TO INSTALL
Download the zip;
Unpack the zip in a folder;
Reboot the OnePlus 6 in fastboot mode (Power and volume-);
Connect the OnePlus 6 to PC;
Run flash-all.bat the folder where you unzipped the ROM;
Wait until the process end.
All roms on AFH: https://www.androidfilehost.com/?w=files&flid=271877
All roms on Google Drive: https://drive.google.com/open?id=1QH...uXp1qf7zIeYN3t
OSX - Linux
If you want to flash these fastboot roms through OSX or Linux you can follow the guide on this post: https://forum.xda-developers.com/sho...0&postcount=56
Remember to install adb and fastboot before flash the rom.
"Invalid sparce file format at header magic" is not an error, you need to wait a bit when you see that string, just wait.
If you want you can use also my tool to unlock bootloader, flash twrp or to understand if the device is recognized: https://toolaio.tk/
Thanks to @SaiBork for first time tested
If you got some problems like write error or no partition, check this: https://forum.xda-developers.com/sho...5&postcount=34