Unable to inject image on Mac

[knrt10]

System config

Operating system: MacOS
Docker version: 19.03.12
Go version: go1.14.3

Steps to reproduce

# create a simple container
$ docker run -d joshwget/sleeper /sleeper

# get latest running container
$ latest_container=$(docker ps -ql)

# run injecto either from docker or built from go
injecto alpine $latest_container

Desired

It should work correctly

Actual result