I have a MacBook Pro running macOS Mojave and an external SSD with Ubuntu installed on it. The way I swapped between macOS and Ubuntu was by pressing the Option/Alt during boot to choose between Macintosh and EFI Boot (when the EFI Boot was selected it booted Ubuntu automatically).
Now I have installed Windows with Boot Camp and the EFI Boot has disappeared. Now I can only choose between Macintosh or Boot Camp.
How can I boot into Ubuntu with the external SSD again?
This is the output of running
/dev/disk0 (internal, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *251.0 GB disk0 1: EFI EFI 209.7 MB disk0s1 2: Apple_APFS Container disk1 180.0 GB disk0s2 3: Microsoft Basic Data BOOTCAMP 70.8 GB disk0s3 /dev/disk1 (synthesized): #: TYPE NAME SIZE IDENTIFIER 0: APFS Container Scheme - +180.0 GB disk1 Physical Store disk0s2 1: APFS Volume Macintosh HD 121.0 GB disk1s1 2: APFS Volume Preboot 46.7 MB disk1s2 3: APFS Volume Recovery 509.7 MB disk1s3 4: APFS Volume VM 1.1 GB disk1s4 /dev/disk2 (external, physical): #: TYPE NAME SIZE IDENTIFIER 0: FDisk_partition_scheme *240.1 GB disk2 1: Linux_Swap 8.0 GB disk2s1 2: Linux 40.0 GB disk2s2 3: Linux 192.1 GB disk2s3