The Compatibility Standard describes a collection of non-standard (and often vendor-prefixed) CSS properties and DOM APIs that web browsers need to support for compatibility with the de facto web.
Code of conduct
We are committed to providing a friendly, safe and welcoming environment for all. Please read and respect the WHATWG Code of Conduct.
Please add your name to the Acknowledgments section in your first pull request, even for trivial fixes. The names are sorted lexicographically.
If you want to preview the spec locally, you can either use a locally installed copy of
Bikeshed by running
make or use the HTTP API version by
If you want to do a complete "local deploy" including commit and/or branch snapshots, run
Run the following steps to enable fancy-mode (which will run
make every time
compatibility.bs is changed on the filesystem).
Step 0. Install Node.js and npm Step 1: Run the following commands
npm install npm run watch
Contributions are welcome, so long as you agree to the CC0 license.