Responsive Checker – Device Preview, Developer Tools & Site Testing

Frank Responsive Checker is a complete device preview, responsive check, and site testing tool for website responsive design and front-end performance directly inside your WordPress dashboard. Test and analyze how your website looks and functions in every possible device — including smartphones, tablets, laptops, desktop monitors, and 4K displays. By simulating 13+ specific device viewports and custom screen resolutions, these developer tools streamline the debugging process for developers, designers, and website owners. Whether you are performing a design audit, checking website accessibility, running site testing across custom breakpoints, or conducting a full website responsive check in every possible device layout, this plugin provides a native testing environment without requiring third-party subscriptions or external applications. How this plugin works: Check Docs

1.1.0

• Date: 8 June 2026
• Fixed screenshot capture to output images matching the visual frame size instead of rendering at full device resolution.
• Fixed DOM Inspector coordinate accuracy on scaled device frames so element detection aligns with the cursor.
• Fixed desktop viewport rendering to show true device layouts using CSS transform scaling instead of shrinking the iframe.
• Inspector highlight overlay now correctly accounts for both display scaling and zoom level.
• Fixed compare mode viewport rendering to show true device layouts using CSS transform scaling and adjusted initialization timing.
• Fixed device selection dropdowns in compare mode for devices containing quotation marks in their names (e.g. iPad Pro 13", Laptop 13").
• Fixed mockup generator capture to support scroll coordinates and synchronise scroll positions with the active preview.
• Fixed network speed selection to automatically reload the page and trigger load-time speed simulation tracking.

1.0.6

• Date: 6 June 2026
• Added frontend responsiveness checking button to settings panel.
• Fixed icon alignment for setting dashboard buttons.
• Fixed vertical alignment and spacing for Go URL navigation button in responsive frame dashboard.
• Fixed z-index layering issue making add device popup render behind the fullscreen panel.
• Fixed disappearing Add Device button bug when custom devices list is updated.
• Added scroll coordinates support to html2canvas captures to output scrolled layouts accurately.
• Added interactive full-screen slide lightbox viewer for gallery screenshots with swipe/keyboard navigation (Esc, Left/Right arrows).
• Updated device lists to include the latest modern devices (e.g., iPhone 15, Laptop 15") and removed obsolete options.
• Fixed iframe navigation history tracking to properly enable Back and Forward buttons during testing.
• Fixed conflict with duplicate "Compare" buttons in the toolbars by assigning distinct UI action classes.
• Fixed CSS conflict that was hiding the side-by-side comparison panels.
• Fixed User-Agent spoofing to immediately apply and properly emulate mobile browsers using client-side injection and a background proxy.
• Added HTTP fallback for the User-Agent copy button to support local development environments.
• Overhauled Touch Mode to add true interactive event forwarding, drag-to-scroll support, and perfect pointer accuracy.
• Fixed encoding issues displaying corrupted text (mojibake) across the plugin UI.
• Fixed cross-iframe media query evaluation errors to accurately scan and extract CSS breakpoints.
• Fully implemented Baseline saving and Visual Comparison diff overlays with local storage support and UI clear actions.
• Fixed device frame resizing calculations for accurate em/rem to pixel conversion when jumping to breakpoints.
• Improved Fullscreen layout by separating Responsive and Developer controls into two distinct floating toggle buttons.
• Moved Exit Fullscreen button to the bottom right to avoid overlapping developer side-panel close buttons.

1.0.4

• Fixed double script execution issue in WordPress backend when admin bar is active.
• Moved admin settings styles and scripts to load exclusively on the plugin settings and documentation pages.

1.0.3

• Removed custom CSS input to follow WordPress security guidelines.

1.0.2

• Updated script loading to meet WordPress guidelines.
• Fixed security nonce issues in AJAX requests.
• Moved styles to external files for faster load times.

1.0.1

• Added device preview screenshots and regression tools.
• Added side-by-side comparison with sync scrolling.
• Added custom viewports and user agent testing.
• Added accessibility contrast checks and focus maps.
• Added temporary links to share layout tests.
• Added developer console logs and media query lists.

1.0.0

• First release of the plugin.