FP4 stuck in Recovery Mode + broken power button = can't proceed

Thank you so much for your reply!

I had already tried fastboot, but I didn’t realize that the “recovery mode” screen is different from the “fastboot mode” screen. Thanks to your suggestion to hold down the “volume down” button while connecting the phone, I figured out how to enter fastboot mode.

This made me take a huge step forward.
I then realized that my computer was not detecting the phone (pressing win+X, device manager, I could see the yellow error icon next to “Android device”). So I installed a driver following this procedure:

  1. download from Get the Google USB Driver  |  Android Studio  |  Android Developers

  2. manually select the driver, looking for android_winusb.inf in the downloaded folder.

At this point I can run “fastboote devices” and check that my phone is recognized by the pc and I can run “fastboot reboot”. Unfortunately “fastboot reboot” reboots the phone and brings me back to the recovery mode screen. So it means that rebooting is not enough and that I should factory reset.

Any other command, like fastboot -w does not work, because the phone is locked.

I tried the ways suggested in these posts:

but so far I have not had success.