I've followed the steps to install graphene on a new P6 pro from the official guide however I get "Error: Failed to execute 'open' on 'USBDevice': Access denied." when trying to unlock the bootloader.
I'm using Manjaro, though I had the same problem with Fedora.
I tried turning on USB debugging mode, allowed USB media transfer and updating to android 13 but with the same result (actually now on Fedora it won't get detected at all when in fastboot, same with Windows).
In subsequent tries I noticed that when the phone gets detected I get "paired" next to phone's name.
In the fastboot screen it says UART disabled, don't know if it means anything.
I've yet to try with another cable as I only have one with USBC and USB, I'll be trying with the one that came with the Pixel Phone with an adapter, however it gets detected fine when connected regularly outside of fastboot (also in Fedora and Windows).
The browsers I've used are Brave and Chromium.
Thanks in advance for any help.