public static void highlightDifferences(List<ValidatableLine> left,
			List<ValidatableLine> right) {

		if (left.size() != right.size()) {
			// update this method to handle different sizes if there is a use case (see the
			// history)
			throw new IllegalArgumentException("Line list size must be the same");
		}

		int sharedLength = Math.min(left.size(), right.size());
		for (int i = 0; i < sharedLength; i++) {
			ValidatableLine line = left.get(i);
			ValidatableLine otherLine = right.get(i);

			line.setValidationLine(otherLine);
		}
	}
Copies from the source to the destination all lines that are not placeholders.  If the 
two input lists are not the same after the copy, then the smaller list is padded with
placeholder lines.
Ghidra/Features/Base/src/main/java/ghidra/app/util/html/diff/DataTypeDiffBuilder.java