Configuration folder is created under $HOME/SmartDashboard

[modelmat]

This clogs up the $HOME directory. Discussions with others in the FIRST Robotics Discord server suggested the ~/wpilib/<year>/tools/SmartDashboard directory.

This is set with https://github.com/wpilibsuite/SmartDashboard/blob/5dea736f714d1854b029578d02ee52ae3f1feebb/src/main/java/edu/wpi/first/smartdashboard/gui/DashboardPrefs.java#L21-L22 as well as https://github.com/wpilibsuite/SmartDashboard/blob/5dea736f714d1854b029578d02ee52ae3f1feebb/src/main/java/edu/wpi/first/smartdashboard/extensions/FileSniffer.java#L27

This can be fixed with the following code (for the former at least)

 public class DashboardPrefs implements PropertyHolder {
   private static final File USER_HOME = new File(System.getProperty("user.home"));
-  private static final File USER_SMARTDASHBOARD_HOME = new File(USER_HOME, "SmartDashboard");
+  private static final String WPILIB_YEAR = "2020";
+  private static final File USER_WPILIB_HOME = new File(USER_HOME, "wpilib/" + WPILIB_YEAR);
+  private static final File USER_SMARTDASHBOARD_HOME = new File(USER_WPILIB_HOME, "/tools/SmartDashboard");

However, SmartDashboard does not seem to store a version number anywhere. I am not experienced enough with Java to figure out how to include this and would ask someone to point me in the right direction or (much easier) just add it themselves.