Adds HTML and CSS features that are in current web specs and ship in at least one browser, but are missing from VS Code's built-in data. See CONTENTS.md for the full list.
Features
Completions and value completions for the added CSS properties, at-rules, pseudo-classes and pseudo-elements, and HTML elements and attributes.
Hovers with browser support and Baseline status.
No false "Unknown property" or "Unknown at rule" warnings.
Descriptions from the spec for built-in CSS properties that VS Code ships with an empty one.
Works in every window, with or without a folder open. The CSS data also applies to SCSS and Less.
Settings
Setting
Description
webSpecAdditions.css.level
How much CSS to add. Each level includes the ones before it.
webSpecAdditions.html.level
How much HTML to add. Each level includes the ones before it.
webSpecAdditions.css.proprietary
Also add vendor-prefixed and non-standard CSS features.
webSpecAdditions.html.proprietary
Also add vendor-prefixed and non-standard HTML features.
Levels:
Off: VS Code's built-in data only.
Baseline: features that are newly or widely available across browsers.
Standardized (CR or higher): also features in a spec at Candidate Recommendation or later, or a WHATWG Living Standard.
Editor's Draft (default): also features only in Working Drafts, Editor's Drafts or Community Group drafts.
A change applies after a window reload. These settings can't hide VS Code's own built-in data.
How it works
New items are declarative custom data (html.customData, css.customData).
extension.js applies the settings and adds a small hover provider. VS Code can't change the description of a CSS property it already knows, so for built-in properties with an empty description, the provider shows one from the spec instead.
Data sources
CSS syntax and facts: w3c/webref (extracted from the specs).
