@SuppressWarnings("unused")
	private Highlight[] getSpecificCommentHighlights(VTMarkupType commentType, String text,
			Object obj, int cursorTextOffset, Highlight[] highlights) {
		CodeUnit cu = (CodeUnit) obj;
		Address minAddress = cu.getMinAddress();
		HashMap<VTMarkupType, VTMarkupItem> typeMap = map.get(minAddress);
		if (typeMap != null) {
			VTMarkupItem markupItem = typeMap.get(commentType);
			if (markupItem != null) {
				VTMarkupItemStatus status = markupItem.getStatus();
				StringStringable value =
					(StringStringable) ((isSource || markupItem.canUnapply())
							? markupItem.getSourceValue()
							: markupItem.getOriginalDestinationValue());
				String comment = value.getString();
				if (comment != null) {
					int startIndex = text.indexOf(comment);
					if (startIndex >= 0) {
						int endIndex = startIndex + comment.length() - 1;
						Color highlightColor =
							getMarkupBackgroundColor(cursorTextOffset, markupItem, startIndex,
								endIndex);
						Highlight highlight = new Highlight(startIndex, endIndex, highlightColor);
						highlights = new Highlight[] { highlight };
					}
				}
			}
		}
		return highlights;
	}
Creates a darker shade of the color passed-in, based on the given amount.

algorithm: 1) grab individual rgb elements
           2) multiply each by a factor.
           
           ie: int newRed = (int)(oldRed * 0.85);

@param color the color to shade
@param amount number between 0..1 (the smaller the number, the darker the shade)
@return the new color
Ghidra/Features/VersionTracking/src/main/java/ghidra/feature/vt/gui/duallisting/VTDualListingHighlightProvider.java