private ID getClosestID(URL url) {
			HelpModel helpModel = toc.getModel();
			HelpSet helpSet = helpModel.getHelpSet();
			Map combinedMap = helpSet.getCombinedMap();
			return combinedMap.getClosestID(url);
		}
Our hook to install our custom cell renderer.
Ghidra/Framework/Help/src/main/java/help/CustomTOCView.java