Chapter Schedule Predictor by Mason

Chapter Schedule Predictor reads the chapter list already on the page and works out when the next update is likely to post — no external services, no tracking, no data ever leaves your browser.

Built-in support for:
- Royal Road fiction pages
- SpaceBattles and other XenForo forums, via a thread's Threadmarks page
- Patreon-style creator post listings

For everything else, it automatically looks for a repeated list of dated entries (chapters, episodes, forum posts) on the page, and once it's confident it's found one, it gets to work — so it also picks up many other fan-fiction hubs, webcomic archives, blog-style serials, and forums with no extra setup needed.

Once it has enough release history (about 3+ release days spanning at least a week), the panel shows:
- A live countdown to the next expected chapter, in both your local time and UTC
- The detected weekly pattern (e.g. "Mon, Wed, Fri") or release interval (e.g. "Every 2 weeks") for slower series
- A reliability score, weighted so recent behavior counts more than older history
- A release calendar heatmap and a chart of how release timing has drifted over time
- A heads-up when a chapter is running late

Everything is computed locally from what's already loaded on the page. Click the toolbar icon to show or hide the panel on any site.