private void clearCodeViewerDiffMarkers() {
		if (p1DiffMarkers == null) {
			return;
		}

		MarkerService markerService = tool.getService(MarkerService.class);
		if (markerService == null) {
			return;
		}

		markerService.removeMarker(p1DiffMarkers, primaryProgram);
		p1DiffMarkers = null;
	}
Reload the marked differences in the diff panel.
Ghidra/Features/ProgramDiff/src/main/java/ghidra/app/plugin/core/diff/ProgramDiffPlugin.java