Cannot resize EXT4 partition on Mac

[brad]

New user here, hoping to be able to stop booting into Linux every time I want to do anything with an EXT filesystem.

Anyhow, I am trying to shrink and existing filesystem, and I am running into an error with no description. Can anyone tell me what I'm doing wrong?

First I resize the partition, leaving a little space, but mostly creating a lot of freespace at the end

step1.jpg

Then, I hit apply operations

step2.jpg

Then I am greeted with a less than descriptive error...

step3.jpg

Any help would be appreciated! I'm eager to find software that does what this this seems to do, so I hope I am simply doing something dumb!

[brad]

Also worth noting, I've installed the Paragon ExtFS for Mac trial as well to see if that would help. It does not appear to...