We're really happy to accept contributions to the mdn-browser-compat-data repository! This file lists some general guidelines to help you contributing effectively.
There are many ways you can help improve this repository! For example:
- Adding new compat data: familiarize yourself with the schema and read the schema docs to add new files.
- Fixing existing compat data: maybe a browser now supports a certain feature. Yay! If you open a PR to fix a browser's data, it would be most helpful if you include a link to a bug report or similar so that we can double-check the good news.
- Fixing a bug: we have a list of issues, or maybe you found your own.
- Reviewing a pull request: there is a list of PRs. Let us know if these look good to you.
You can use npm test
to validate data against the schema. You might need to install the devDependencies using npm install --only=dev
.
The JSON data is validated against the schema using ajv
.
If the feature you're interested in is a JavaScript API, you can cross-reference data against the Web API Confluence Dashboard using the confluence
npm script. This script will overwrite data in your current working tree according to data from the dashboard.
Note: Web API Confluence Dashboard data should not be regarded as perfect knowledge of JavaScript APIs.
The dashboard derives its data from the JavaScript object graph on a sample page loaded in each browser. For example, an own property named URL
on Document.prototype
implies the "Document
interface has a member named URL
. For various reasons, not all APIs are exposed on JavaScript prototypes, even when the API is available in the browser.
Examples:
# Load confluence data for ServiceWorker
npm run confluence -- --interfaces=ServiceWorker
# Fill in missing/ambiguous Firefox data on known interfaces
npm run confluence -- --browsers=firefox --fill-only
# Print documentation on full list of options
npm run confluence -- --help
You can use npm run render $query $dept $aggregateMode
to output the table HTML as it would be rendered on MDN.
The parameters are the same as the {{compat}}
macro.
Paste the generated HTML into the MDN editor (source mode). You can use a new page, for example: https://developer.mozilla.org/en-US/docs/new and verify if the output looks correct.
Not everything is enforced or validated by the schema. A few things to pay attention to:
- Feature identifiers (the data namespaces, like
css.properties.background
) should make sense and are spelled correctly. - Nesting of feature identifiers should make sense.
- Notes use correct grammar and spelling. They should be complete sentences ending with a period.
The JSON files should be formatted according to the .editorconfig file.
Please note that the compatibility data is made available under the CC0 license, so any contributions must be compatible with that license. If you're not sure about that, just ask.
If you need help with this repository or have any questions, contact the MDN team in the #mdn IRC channel on irc.mozilla.org or write us on discourse.