private boolean overviewContains(int index) {
		for (int i = 0; i < MARKER_HEIGHT; i++) {
			if (overview.contains(index - i)) {
				return true;
			}
		}
		return false;
	}
Get the tooltip for the marker at the specified index and address

@param addr address of item to navigate to
@param x x location of cursor
@param y y location of cursor

@return tool tip string, null if no tool tip
Ghidra/Features/Base/src/main/java/ghidra/app/plugin/core/marker/MarkerSetImpl.java