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Cat Gatekeeper

Chrome extension by developmentbycores · Productivity · Tools

  • Established publisher

A Chrome extension in Productivity · Tools with 1 000 users, a small but real audience.

Every site you visit. This extension can read and change the content of any page you open.

What the developer says, and 4 screenshots

Loading from the Chrome Web Store. Open the listing if it does not appear.

Users
1 000
Rating
5.0 (7 ratings)
Users, last 15 days
unchanged
Rating, last 30 days
Not watched long enough to say
Version
1.0.0
Updated in the store
2026-06-01
Published
2026-06-01
Manifest
V3
Browser access
4 permissions, 1 site pattern

How it has moved

Users
unchanged since 01.09
1k · 2 readings
  1. 2026-09-011k
  2. 2026-09-151k
Rating
unchanged since 01.09
reviewsrating 5.00 · 2 readings
  1. 2026-09-01reviews7rating5.00
  2. 2026-09-15reviews7rating5.00
Users
unchanged since 01.09
1k · 2 readings
  1. 2026-09-011k
  2. 2026-09-151k
Rating
unchanged since 01.09
reviewsrating 5.00 · 2 readings
  1. 2026-09-01reviews7rating5.00
  2. 2026-09-15reviews7rating5.00

A dot marks a day the store showed a different number. Between them the line carries the last one forward: we read every listing more than once a day and record a point only when something moves. History beyond ninety days is in the app.

What it can reach

Every site you visit. This extension can read and change the content of any page you open.

  • See the address and title of every tab you have open tabs
  • Run its own code on the pages it can access scripting
  • Schedule work to run later alarms
Show the remaining 1
  • Store data in your browser storage

The full permission history for this extension

What changed recently

Nothing has moved on this listing since we started watching it.

The publisher

developmentbycores publishes 10 listings we track, 47k users between them.

  1. Disable YouTube Shorts developmentbycores · Productivity · Workflow · published 2024-02-22 20k users ★ 3.2
  2. UnHook YouTube developmentbycores · Productivity · Tools · published 2024-03-12 10k users ★ 4.6
  3. Authenticator App developmentbycores · Productivity · Tools · published 2024-05-03 10k users ★ 3.8
Show 5 more from this publisher
  1. Block Porn developmentbycores · Productivity · Tools · published 2024-09-01 2k users ★ 4.2
  2. Currency Exchange Rate developmentbycores · Lifestyle · Household · published 2024-06-25 2k users ★ 5.0
  3. Block Sites developmentbycores · Productivity · Workflow · published 2024-03-20 725 users ★ 4.0
  4. UTC Time Converter developmentbycores · Productivity · Tools · published 2024-07-13 614 users ★ 5.0
  5. Clipboard History developmentbycores · Productivity · Tools · published 2024-11-15 347 users ★ 5.0

Like this one

Listings the catalog judges closest in what they say they do.

  1. pon-blocksite | Site blocker, free forever Describes nearly the same job, smaller audience 17 users
  2. Blockodile: Block Sites, Shorts & Reels Describes nearly the same job, smaller audience 3k users ★ 4.3
  3. Zen Guard Describes nearly the same job, smaller audience 3 users
  4. Yield: Website Focus Guard Describes nearly the same job, smaller audience 3 users
  5. Site Blocker Describes nearly the same job, smaller audience 608 users ★ 4.5

The top 5 only. The full comparison, with why each one is close, is on the alternatives page; ranking a whole neighbourhood by your own criteria is in the app.

Is this your extension?

Connect it to Ext Ops Panel and see installs, uninstalls and uninstall reasons as events arrive, not as a weekly summary.

See what the panel does

Figures come from our own daily pass over the public Chrome Web Store listing, last read on . We publish no contact details for extension developers.