What is the difference between BIGTREE_OCTOPUS_V1 and BIGTREE_OCTOPUS_V1_USB

When building Marlin firmware for the BigTreeTech Octopus from the official BigTreeTech GitHub repository Marlin directory, you can see two different targets in PlatformIO:


It is not immediately made clear what the difference between those is, but a short description can be found in ini/stm32f4.ini:

BIGTREE_OCTOPUS_V1_USB has support for using USB flashdrives directly on the board and serial-over-USB while BIGTREE_OCTOPUS_V1 has not.

In most cases, you want to build BIGTREE_OCTOPUS_V1_USB if printing via USB (e.g. via Octoprint) because the BIGTREE_OCTOPUS_V1 configuration does not allow printing via USB.
The compiler definitions for BIGTREE_OCTOPUS_V1 in ini/stm32f4.ini are:
build_flags        = ${stm32_variant.build_flags}
                     -DSTM32F446_5VX -DUSE_USB_HS_IN_FS

whereas BIGTREE_OCTOPUS_V1_USB enabled more USB-related features:

build_flags       = ${stm_flash_drive.build_flags}
                    -DSTM32F446_5VX -DUSE_USB_HS_IN_FS
                    -DUSE_USBHOST_HS -DUSBD_IRQ_PRIO=5