Love it! I've noticed a single issue with themes though. Thread lines have set colors, which wouldn't be a problem unless you are using the solarized dark theme, then the first thread line is really hard to see.
What I did to fix that is simply set it the same border the first thread line uses normally (which is just the section border) that covers the background .comment-level--1 > .expando .threadLine { border: var(--kbin-section-border); border-width: 2px; }. It also fixes inconsistency between default kbin themes and custom-made ones. Before and after