@Override
	public void optionsChanged(ToolOptions options, String optionName, Object oldValue,
			Object newValue) {
		if (optionName.equals(SNAPSHOT_PERIOD_OPTION)) {
			synchronized (this) {
				int oldSnapshotPeriod = snapshotPeriodMin;
				int newSnapshotPeriodMin =
					options.getInt(SNAPSHOT_PERIOD_OPTION, snapshotPeriodMin);
				if (newSnapshotPeriodMin < 0) {
					throw new OptionsVetoException("The snapshot period must be >= 0");
				}
				snapshotPeriodMin = newSnapshotPeriodMin;
				if (oldSnapshotPeriod != snapshotPeriodMin) {
					reportTimerSetting();
					if (oldSnapshotPeriod == 0 || timerStart > 0) {
						// Fix current running timer
						if (snapshotPeriodMin > 0 && timerStart > 0) {
							totalDelayTime = (int) ((new Date()).getTime() - timerStart);
						}
						startSnapshotTimer(false);
					}
				}
			}
		}
	}
Initialize the look and feel options.
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/misc/RecoverySnapshotMgrPlugin.java