New chapters and sections

[bartveneman]

Year-over-year comparison summary chapter

A dedicated chapter (placement TBD, likely near the Conclusion) that rolls
up the 2026→2027 deltas across all the other chapters into one place.
Individual chapters would still call out their own year-over-year changes
inline — this chapter is the highlights/summary rollup of those, not a
replacement for them.

"Rising stars" section

Based on Baseline
status adoption (inspired by this post).
Compare 2026 vs. 2027 data and highlight features with meaningful adoption
growth — and the inverse: features that are being used significantly less.

Web Components / Shadow DOM chapter

Centered on adoptedStyleSheets — constructed stylesheets adopted into
shadow roots via JavaScript. These never appear in served HTML/CSS, so they
can only be captured with headless-browser-based scraping, a methodology
change planned for 2027.

Note: other web-component signals — custom-element selectors (tag names
containing a hyphen), ::slotted(), :host/:host-context() — are
already detectable with today's static CSS analysis and don't require a
headless browser. This chapter would specifically cover what headless
scraping newly unlocks: adoptedStyleSheets access.