Step 1: Describe the problem:

Steps to reproduce:

1. Open Demo
2. Run the lighthouse performance audit

Observed Results:

• You should see Avoid an excessive DOM size (3,458 elements) error

This is because of the use of the HTML tables which add a few layers of depth to the DOM tree. With more complex usages this number can grow up to 10k+. I don't think this problem can be completely solved because highlight.js adds a lot of HTML elements but it should be possible to lower this number a bit by avoiding the <table> element. Proof of concept is browser visual studio code diff which uses only a combination of divs and spans.

I am going to spend some time on this issue to see what are potential cons of this approach.