Interestingly, it was not present in the initial release. It was added here: https://github.com/raspberrypi/pico-bootrom/commit/ad55537bf35e332503b950d6951c41bc

Interestingly, it was not present in the initial release. It was added here: https://github.com/raspberrypi/pico-bootrom/commit/ad55537bf35e332503b950d6951c41bcb8a7954f#diff-1bcdd4109020ba4c51666828150569e2bf550f4c3265b476175ba7375c8bf214R395-R398 https://github.com/raspberrypi/pico-bootrom/commit/ad55537bf...