Autoprefixer Browserslist Error - Fix in CI

By Kaveh Alemi·Latchkey

Autoprefixer reads target browsers from browserslist. A stale caniuse-lite or a query it cannot parse makes it warn loudly or error, which a strict CI escalates to a failure.

What this error means

The build prints Browserslist: caniuse-lite is outdated or Unknown browser query. Under warnings-as-errors it fails the job.

Browserslist: caniuse-lite is outdated. Please run:
  npx update-browserslist-db@latest

Error: Unknown browser query `last 2 verions`. Maybe you meant `last 2 versions`?

Common causes

Outdated caniuse-lite

The committed lockfile pins an old caniuse-lite, so autoprefixer warns the data is stale.

Malformed browserslist query

A typo in .browserslistrc or the browserslist field (e.g. last 2 verions) cannot be parsed.

How to fix it

Update the caniuse-lite database

1. Run the official updater and commit the lockfile change.

npx update-browserslist-db@latest

Fix the browserslist query

1. Correct the query syntax in your config.

# .browserslistrc
last 2 versions
> 0.5%
not dead

How to prevent it

• Schedule periodic update-browserslist-db runs so the data never goes stale.
• Validate browserslist queries against the documented syntax.

Frequently asked questions

Related guides

References

• Node.js documentation
• npm CLI documentation
• GitHub Actions documentation