Ext4 is a linux file system, you would need third party software to use it with macOS so unless you specifically need to use that file system either exFAT or HFS+ (listed as Mac OS Extended (Journaled) in disk utility) would be a better option. I have been affected by an ext4 unmountable problem. The suggested solution is to run e2fsck in a live CD. Ubuntu can't be used because it periodically tries to mount the partition (/dev/sda3 in my case) preventing e2fsck from running.
Disk Utility on Mac supports several file system formats:
ExtFS for Mac by Paragon Software allows the user to read and write extFS-formatted files on a Mac computer. Read or write files from HDD, SSD or flash drives formatted under Linux ext2, ext3, and ext4 file systems. Just connect the disk and access the files. All this comes in handy with a lightweight menu bar.
Apple File System (APFS): The file system used by macOS 10.13 or later.
Mac OS Extended: The file system used by macOS 10.12 or earlier.
MS-DOS (FAT) and ExFAT: File systems that are compatible with Windows.
Apple File System (APFS)
Apple File System (APFS), the default file system for Mac computers using macOS 10.13 or later, features strong encryption, space sharing, snapshots, fast directory sizing and improved file system fundamentals. While APFS is optimised for the Flash/SSD storage used in recent Mac computers, it can also be used with older systems with traditional hard disk drives (HDD) and external, direct-attached storage. Librarian pro 4 0 – complete personal inventory system download. macOS 10.13 or later supports APFS for both bootable and data volumes.
APFS allocates disk space within a container on demand. The disk’s free space is shared and can be allocated to any of the individual volumes in the container as needed. If desired, you can specify reserve and quota sizes for each volume. Each volume uses only part of the overall container, so the available space is the total size of the container, minus the size of all the volumes in the container.
Choose one of the following APFS formats for Mac computers using macOS 10.13 or later.
APFS: Uses the APFS format.
APFS (Encrypted): Uses the APFS format and encrypts the volume.
APFS (Case-sensitive): Uses the APFS format and is case-sensitive to file and folder names. For example, folders named “Homework” and “HOMEWORK” are two different folders.
APFS (Case-sensitive, Encrypted): Uses the APFS format, is case-sensitive to file and folder names and encrypts the volume. For example, folders named “Homework” and “HOMEWORK” are two different folders.
You can easily add or delete volumes in APFS containers. Each volume within an APFS container can have its own APFS format — APFS, APFS (Encrypted), APFS (Case-sensitive) or APFS (Case-sensitive, Encrypted).
Mac OS Extended
Choose one of the following Mac OS Extended file system formats for compatibility with Mac computers using macOS 10.12 or earlier.
Mac OS Extended (Journaled): Uses the Mac format (Journaled HFS Plus) to protect the integrity of the hierarchical file system.
Mac OS Extended (Journaled, Encrypted): Uses the Mac format, requires a password, and encrypts the partition.
Mac OS Extended (Case-sensitive, Journaled): Uses the Mac format and is case-sensitive to folder names. For example, folders named “Homework” and “HOMEWORK” are two different folders.
Mac OS Extended (Case-sensitive, Journaled, Encrypted): Uses the Mac format, is case-sensitive to folder names, requires a password, and encrypts the partition.
Windows-compatible formats
Choose one of the following Windows-compatible file system formats if you are formatting a disk to use with Windows.
MS-DOS (FAT): Use for Windows volumes that are 32GB or less.
ExFAT: Use for Windows volumes that are over 32GB.
Ext4 Macbook Pro
See alsoPartition schemes available in Disk Utility on MacAbout Disk Utility on Mac