Baobab running in a docker container with NoVNC to figure out what is taking up space on a headless server.
docker run -it -v /place/to/mount:/data -p 6080:6080 jessedusty/baobab
Then open a web browser and goto http://<server-ip/dns>:6080
You can set the resolution/bit-depth using the environment variable $RESOLUTION_BIT_DEPTH. The default ix 1600x900x16.