testing-web-responsive

Launch a browser, navigate to the target URL, then run the responsive sweep with a breakpoint list such as 375×812, 768×1024, and 1280×720. The tool screenshots each viewport, checks for horizontal overflow, and records a pass or warning result per breakpoint.

The webmobai_test_responsive tool checks whether document.documentElement.scrollWidth exceeds clientWidth at each viewport, flagging horizontal overflow as a warning. Overflow is usually caused by fixed-width images, tables, or embeds missing max-width: 100%.

No. Resizing only changes CSS viewport dimensions — it does not enable touch events, change the User-Agent, throttle CPU or network, or adjust devicePixelRatio. For device emulation, relaunch the browser with a Playwright device preset like iPhone 13 or Pixel 5.

Launch the browser with a storage_state_path pointing to a captured authentication session file, then navigate and confirm the final URL is not the login page before running the sweep. Sweeping a login page produces a misleading green result since login pages are trivially responsive.

A false pass typically happens when the sweep ran against a login redirect instead of the real page, or when a fixed element visually overflows via transform without increasing scrollWidth. Verify the final URL after navigation and inspect screenshots for elements the scrollWidth check cannot catch.

Viewport resizing cannot test touch gestures like swipe or long-press, does not change window.screen values, and screenshots render at CSS resolution rather than real device pixel density. For real hardware behavior, use a device farm like BrowserStack or a physical device.