@Override
	protected void programActivated(Program program) {

		program.addListener(this);
		program.addTransactionListener(transactionListener);
		updateForDomainFileChanged();

		createMarkerSets(program);
		intializeChangeMarkers();
	}
Manages the markers to display areas where changes have occurred
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/misc/MyProgramChangesDisplayPlugin.java