Polypane is a desktop application that lets web developers preview their work in multiple viewports at once, which is essential for good responsive web design. Built using OpenJS’s Electron, Polypane offers all of the web content rendering and inspection benefits Chromium provides, plus a number of unique features such as automated media breakpoint detection, measurement rulers, one-click screenshotting of individual viewports, and more. Earlier this year, Polypane’s creator, Kilian Valkh...
