spring-onion
first i re-ran the command to stop fwupd as I had shut down the pc, then tried the unlock bootloader button and i get this "Error: Failed to execute 'open' on 'USBDevice': Access denied."?
Pixel is in fastboot mode

    Did you install the android-sdk-platform-tools-common package? Make sure Brave isn't installed as a snap or flatpak.

      spring-onion Well I think there is a problem as Zorin only has Brave as a snap or flat, I think I installed the flatpak. I just search the app store I don't get anything for "android-sdk-platform-tools-common package" is this the exact name?

        spring-onion I just tried to install "android-sdk-platform-tools-common" and I got "command not found"

          It's not an app so it won't show up there, you should be able to install it manually in the command prompt with:

          sudo apt install android-sdk-platform-tools-common package

          But that's unlikely to let you proceed with the installation without hiccups since your browser is still a flatpak. Do you have another Android phone in reach by any chance? If it's relatively modern it's likely you can use that as the host device. Simply open the web installer there and connect that phone with your pixel.

            spring-onion I have installed this package now, I must of missed a bit of the command. I'm thinking I will uninstall Brave and re-install as a .deb?

                Rand-Uzer I do have a perfectly functioning Samsung A04, these are getting a bit old now.
                I will try a .deb terminal install of Brave as I've not used it for anything so no big deal to uninstall

                  Sounds good. If it doesn't go anywhere I would definitely try with the Samsung, from my brief research it might fulfill the requirements. If you go down that route, the only difference regarding the install process will be that you will have to keep tapping reconnect on the Samsung during various steps of the installation.

                    spring-onion I just installed Brave via terminal so I will try again and keep you posted. If no joy I will try the Samsung
                    Thanks a lot for the assistance so far, I do feel I'm getting closer (famous last words lol)

                      spring-onion One question, do I need to change usb settings for this to work, eg transfer files or in developer menu verify apps over usb? With the Samsung

                        spring-onion Well I have got further, I'm at download release and I got this ..."Error undefined"

                          spring-onion On the Samsung? Not even close to that, looks like I will need to do a heck of a lot of deleting and transfering., not sure I can get to 32 gigs on the Samsung

                            spring-onion Well I deleted all photos and videos, deleted most apps and no way the phone can do it as it's telling me there is only 32 g total storage and I can only get it to 14.3 gb available ...

                            How hard is the command line install? Is it copy commands all the way?

                              It should be pretty reasonable, just make sure you download and flash the correct release.