@Override
	public synchronized void projectClosed(Project project) {
		if (currentProject != null) {
			stopSnapshotTimer();
			currentProject.getProjectData().removeDomainFolderChangeListener(fileListener);
			pendingSnapshotSet.clear();
			fileSet.clear();
			currentProject = null;
		}
	}
Tells a plugin that it is no longer needed.  The plugin should remove itself
from anything that it is registered to and release any resources.  Also,
any plugin that overrides this method should call super.dispose().
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/misc/RecoverySnapshotMgrPlugin.java