Ext Ops Panel
Open the app

Responsive Tester - Mobile View, Breakpoint Checker & CSS Editor

Chrome extension by Mr Violets · Productivity · Developer

A Chrome extension in Productivity · Developer with 45 users, barely installed.

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

What the developer says, and 3 screenshots

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

Users
45
Rating
not rated yet
Users, last 17 days
+14
Version
1.9.0
Updated in the store
2026-09-15
Published
2026-07-13
Manifest
V3
Browser access
6 permissions, 1 site pattern

How it has moved

Users
+14 since 01.09
31-45 · 9 readings
2026-09-14: removed from the store2026-09-16: released 1.9.02026-09-16: back in the store
  1. 2026-09-0131
  2. 2026-09-0235
  3. 2026-09-0439
  4. 2026-09-0642
  5. 2026-09-0743
  6. 2026-09-0943
  7. 2026-09-1340
  8. 2026-09-1644released 1.9.0back in the store
  9. 2026-09-1745
Users
+14 since 01.09
31-45 · 9 readings
2026-09-14: removed from the store2026-09-16: released 1.9.02026-09-16: back in the store
  1. 2026-09-0131
  2. 2026-09-0235
  3. 2026-09-0439
  4. 2026-09-0642
  5. 2026-09-0743
  6. 2026-09-0943
  7. 2026-09-1340
  8. 2026-09-1644released 1.9.0back in the store
  9. 2026-09-1745

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.

  • Block or redirect requests on the sites it can access declarativeNetRequestWithHostAccess
  • Run its own code on the pages it can access scripting
  • See when you navigate between pages webNavigation
Show the remaining 3
  • Add items to the right-click menu contextMenus
  • Run work in a hidden page offscreen
  • Store data in your browser storage

The full permission history for this extension

Version history

  1. Version 1.9.0

What changed recently

  1. Back in the store
  2. Package size changed
  3. Store description rewritten
Show the remaining 2
  1. Released version 1.9.0 (was 1.8.0)
  2. Removed from the store

The publisher

Mr Violets publishes 10 listings we track, 79k users between them. Listed website: responsive-tester.app.

  1. Screen Ruler - Measure and Inspect the Web Mr Violets · Productivity · Developer · published 2024-03-29 60k users ★ 4.3
  2. Stay Awake: Keep Your Computer Awake Mr Violets · Productivity · Workflow · published 2023-05-28 10k users ★ 4.7
  3. UI Inspector - Visual CSS Editor Mr Violets · Productivity · Developer · published 2024-11-01 5k users ★ 4.0
Show 5 more from this publisher
  1. Marble: Automatically Organized Tab Groups Mr Violets · Productivity · Workflow · published 2023-08-22 2k users ★ 4.6
  2. Deep Tab Search: Tab Switcher & Search Mr Violets · Productivity · Workflow · published 2024-01-09 870 users ★ 3.2
  3. Quilt - Tiling Window Manager Mr Violets · Productivity · Workflow · published 2023-08-08 789 users ★ 5.0
  4. CSS Viewer - Inspect & Copy Any Element's CSS Mr Violets · Productivity · Developer · published 2026-04-10 478 users
  5. Pointer - Element Inspector for DevTools Mr Violets · Productivity · Developer · published 2025-06-25 208 users ★ 3.0

Like this one

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

  1. Responsive Design Describes nearly the same job, smaller audience 43 users
  2. Responsive Tester — Mobile View by BugCapture Describes nearly the same job, smaller audience 6 users
  3. ScreenLab Describes nearly the same job, smaller audience 14 users ★ 5.0
  4. Be Responsive Describes nearly the same job, smaller audience 384 users ★ 2.3
  5. Responsive Simulator - Multi Device Viewport Tester Describes nearly the same job, smaller audience 12 users

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.