Technical users can view the Public API Docs to understand how the crowdsourced database is queried.
The SponsorBlock GitHub contains the complete logic for how the extension identifies and skips segments.
If you're looking for a specific or the changelog for a different platform (like Chrome or Android), let me know which device you're on!
ajayyy/SponsorBlock: Skip YouTube video sponsors ... - GitHub
Users submit timestamps for segments (sponsors, intros, etc.).
In recent "Plus" or "Lite" versions (like YTLite 5.2.1), the SponsorBlock core was rewritten for better compatibility with YouTube's newer player versions (v19.x.x+) and improved segment skipping.