IDE ignores the value of "$HOME"

[mirage335]

Arduino ignores "$HOME", accepting the "user.home" Java property, apparently kept as "/home/$USER", instead.

Seems to be a common problem with Java applications.
https://stackoverflow.com/questions/32788763/jdk-and-idea-ignores-home-on-ubuntu

For some users, the added complexity may cause problems. For some compiler scripts calling the Arduino IDE, this undocumented behavior might be important.
https://github.com/mirage335/arduinoUbiquitous/blob/master/_prog/core.sh