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Update Scanner

Paid Extension

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What Update Scanner is

Update Scanner is a free, open-source browser extension that watches web pages for changes, including pages without Atom or RSS feeds. You choose how often each site is scanned, and the scanner can ignore minor edits. When it finds an update, a notification panel appears; selecting it opens the page with changes highlighted in yellow. The toolbar lists updated pages, while a sidebar shows changed items in bold with their latest changes. The add-on listing describes full international support. It requires permission to display notifications, access browser tabs, and access data from all websites. The listed license is GNU General Public License version 3.0 only. The maker says Firefox changes led to a rewrite and that some earlier features remain unfinished. Version 4.4.0 was last updated April 24, 2019. The free plan costs nothing and includes configurable checks and minor-change filtering.

Who it suits

It suits people who need page-change alerts for sites without feeds. It is available as an extension and supports configurable scan schedules.

What it does well

Monitors pages without Atom or RSS feeds
Configurable scanning frequency for each site
Highlights detected changes automatically
Can ignore minor page updates
Free and open source

What to know first

Some previous features remain unfinished
Requires broad website and browser permissions
Last listed update was April 24, 2019
No API, SSL monitoring, or status page

Plans

Plan	Billed and limits	Price
Update Scanner	Firefox add-on · page-check frequency is configurable · minor changes can be ignored	Free

As sneakypete81.github.io lists them, read 11 Oct 2026. The maker's own page has the final word.

Verdict

Update Scanner provides focused page monitoring with adjustable checks and change highlighting. Its unfinished rewrite and broad permissions are important considerations before use.

Facts from Update Scanner's own pages

API access: No · addons.mozilla.org, 21 Sept 2026
Change display: Detected changes are highlighted automatically. · addons.mozilla.org, 11 Oct 2026
Check schedule: Users can select how often each site is scanned. · addons.mozilla.org, 11 Oct 2026
Current status: The maker says the extension was rewritten due to Firefox changes and that not all previous features are finished. · sneakypete81.github.io, 11 Oct 2026
Languages: The add-on listing describes full international support. · addons.mozilla.org, 11 Oct 2026
License: The listed license is GNU General Public License version 3.0 only. · addons.mozilla.org, 11 Oct 2026
Minor updates: Users can configure the scanner to ignore minor changes. · sneakypete81.github.io, 11 Oct 2026
Notifications: When an update is detected, a notification panel appears, and clicking it shows changes highlighted in yellow. · sneakypete81.github.io, 11 Oct 2026
Page list: Users can view updated pages from the toolbar and open a sidebar showing updated items in bold and their latest changes. · sneakypete81.github.io, 11 Oct 2026
Permissions: The listing says the add-on requires permission to display notifications, access browser tabs, and access data for all websites. · addons.mozilla.org, 11 Oct 2026
Purpose: Update Scanner monitors web pages for updates, including sites that do not provide Atom or RSS feeds. · addons.mozilla.org, 11 Oct 2026
Support: The maker directs users to the project's GitHub and Issues pages to help with the rewrite. · sneakypete81.github.io, 11 Oct 2026
Version history: The add-on listing shows version 4.4.0, last updated April 24, 2019. · addons.mozilla.org, 11 Oct 2026