In that case, the following from the linked page might be worth making note of:
> To enable USB host boot mode, the Raspberry Pi needs to be booted from an SD card with a special option to set the USB host boot mode bit in the one-time programmable (OTP) memory. Once this bit has been set, the SD card is no longer required. Note that any change you make to the OTP is permanent and cannot be undone.
Not that it matters much to me but still something worth being aware of if you later try to repurpose your RPi for something else I think.
> The Raspberry Pi 3B+ and Compute Module 3+ support USB mass storage boot out of the box. The steps specific to previous versions of Raspberry Pi do not have to be executed.
Then the last one,
> Raspberry Pi 4
>The Raspberry Pi 4 currently requires non-default firmware to enable USB mass storage boot: see the USB mass storage boot section of the Pi 4 Bootloader Configuration page for more information.
But overall, it's possible in some way with all these versions,
>Available on Raspberry Pi 2B v1.2, 3A+, 3B, 3B+, and 4B only.
Anyways, I assume that the following is what you are referring to: https://www.raspberrypi.org/documentation/hardware/raspberry...
In that case, the following from the linked page might be worth making note of:
> To enable USB host boot mode, the Raspberry Pi needs to be booted from an SD card with a special option to set the USB host boot mode bit in the one-time programmable (OTP) memory. Once this bit has been set, the SD card is no longer required. Note that any change you make to the OTP is permanent and cannot be undone.
Not that it matters much to me but still something worth being aware of if you later try to repurpose your RPi for something else I think.