v146 · developer trial · isolated web apps

Unframed mode (f.k.a. borderless)

Isolated Web Apps can opt into "unframed" display mode, painting all the way to the OS window edges — no title bar, no system controls, complete custom chrome. For ambitious desktop-PWA-style experiences that want pixel-perfect control over the whole surface.

concepts

  1. Window Mockup

    Side-by-side rendered mockups of a "standalone" window (the current default) and "unframed" mode, showing the same app in both. Hover over each region to see the responsibility shift to the app.

  2. Virtual Desktop Client

    The motivating use case named in the explainer: a VDI client that needs every pixel for the remote session. Flip between standalone and unframed to see the OS titlebar disappear and the app paint its own integrated chrome edge-to-edge.

  3. Draggable region tester

    Mock window with a switchable framed/unframed chrome and a live pointer-event probe. See where app-region: drag needs to go and which descendants must opt back out.

  4. Drawing Canvas App

    A full-bleed drawing app that shows what unframed mode gains: toggle the browser title bar on and off to see the canvas expand into the reclaimed space. Draw directly, picking colors and brush sizes — all the pixel real-estate that unframed mode unlocks.

why it shipped

Isolated Web Apps target ambitious desktop installs — image editors, communication apps, immersive experiences. The standard PWA window controls overlay was a halfway house: a thin title strip on top, the rest of the window owned by the app. Unframed mode is the next step: no system chrome at all, the app paints every pixel. The trade-off is that the app now has to render its own move handles, close buttons, and minimise / maximise affordances, which means the model is opt-in and gated to IWAs.

references