2027 Web Platform Feature Ranking

Ranked proposals (top = most important)

1. Web app manifest share_target

   Allows an installed web app to appear in the device's share dialog as a target for shared content.
2. Improve interoperability of pointer events on touch devices
3. 103 Early Hints preloading

   Browsers start preconnecting and preloading resources while the server is still generating the page, with consistent resource timing entries.
4. Speculation Rules API

   Hints to the browser to proactively download pages in the background so they appear instantly when the user navigates to them.
5. Single-axis scroll containers

   Such as overflow: scroll clip, which allows position: sticky to work relative to different scroll containers per axis.
6. CSS justify-⁠items and justify-⁠self in block layout
7. Allow CSS transitioning/animating display and content-⁠visibility

   Useful for delaying display: none until an exit animation completes.
8. CSS filter(image, ...filters)

   Takes an image and a filter, and returns a new image.
9. CSS corner-⁠shape property

   Alternative shapes for border-⁠radius, such as squircles and bevels.
10. CSS margin-⁠trim

    Removes the margins of child elements when they meet the edges of the container.
11. JavaScript CSS module imports

    import … with { type: "css" } to load CSS resources as constructable stylesheets.
12. Device Posture API

    Reflects the posture of a device, such as whether a foldable device is folded, in both CSS and script.
13. Progressive rendering of JPEG XL and AVIF images

    Displays a preview version of the image while the rest downloads.
14. Brotli support in CompressionStream and DecompressionStream
15. WebVTT

    WebVTT files are loaded using the <track> element, and the VTTCue API can be used to create or update cues dynamically.
16. CSS @supports at-⁠rule()

    Checks if a CSS at-rule is supported.
17. JavaScript self-profiling API

    The Profiler API records data about the execution of a page, which you can send to a server for later analysis.
18. Timing of cross-origin redirects in the Performance API

    Consistent navigation timing and resource timing entries for cross-origin redirects.
19. CSS border-⁠shape property

    Sets the geometry of the border box to a fully custom shape, changing the shape of borders, outlines, and shadows.
20. CSS align-⁠content for centering in buttons and inputs

    Allows overriding the vertical alignment of text in form controls.
21. Pause media in hidden iframes

    The media-⁠playback-⁠while-⁠not-⁠visible permission policy pauses audible media in iframes that are hidden.