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Preview of Seamprint

Seamprint by nguyenhann3492

Seal a page's structural landmarks locally and reveal what was added, removed, rewritten, or moved when you return.

Available on Firefox for Android™Available on Firefox for Android™
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About this extension
Seamprint remembers the outline of a page rather than archiving the whole page. A sealed impression contains the canonical page address, page title, capture time, and up to 350 visible structural landmarks: headings, buttons, and links in main or article content. Landmark text is normalized and limited to 180 characters. Paragraphs, form values, passwords, media, cookies, full HTML, and screenshots are not captured.

On a return visit, the popup compares the current structure with the locally sealed impression. Exact landmarks can be marked as moved when their sequence changes. Similar landmarks of the same kind can be shown as rewritten. Unmatched landmarks are reported as added or removed. The comparison is deterministic, capped at 80 displayed changes, and is a browsing aid—not a semantic or legal determination that a page’s meaning changed.

Mark on page outlines only current landmarks that participate in added, moved, or rewritten results. It does not reconstruct removed content or modify site data. Seal current state replaces the earlier impression for that canonical address. Forget removes it. Storage is bounded to the 40 most recently sealed pages.

Everything runs locally after the user opens the popup. Seamprint does not crawl pages in the background, send alerts, sync data, use analytics, call artificial intelligence services, or communicate with third parties. Tracking fragments and common campaign query parameters are removed only when calculating the local comparison key; other functional query parameters remain distinct.
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Version
1.0.0
Size
22.54 KB
Last updated
7 days ago (Sep 24, 2026)
Related Categories
  • Web Development
License
Mozilla Public License 2.0
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