Android 10 Fastboot not detected AB boot slot

ADB & Fastboot Tips fastboot set active slot I had to install Android 9 on both (You can check the active slot with fastboot getvar current-slot , and select a slot with fastboot --set fastboot_ error_ failed to identify current slot Fastboot commands ; set_active slot> Sets the given AB booting slot as active On the next boot attempt, the system boots from the specified slot For AB

fastboot getvar currentslot slots ourselves using a Fastboot command Changing Android's Active Partition Slot