private static FileInputStream getAlternateFileInputStream() {
		File previousFile =
			GenericRunInfo.getPreviousApplicationSettingsFile(APPLICATION_PREFERENCES_FILENAME);
		if (previousFile == null) {
			return null;
		}

		try {
			FileInputStream fis = new FileInputStream(previousFile);
			Msg.info(Preferences.class, "Loading previous preferences: " + previousFile);
			return fis;
		}
		catch (FileNotFoundException fnfe) {
			// Ignore so we can try another directory.
		}

		return null;
	}
Gets an input stream to a file that is the same named file within a different 
application version directory for this user. This method will search for an 
alternate file based on the application version directories modification times 
and will use the first matching file it finds.  

@return a file input stream for an alternate file or null.
Ghidra/Framework/Generic/src/main/java/ghidra/framework/preferences/Preferences.java