Include a single module.exports assignment

[desrosj]

This combines the two module.exports assignments to ensure that all desired plugins are run.

This also runs npx update-browserslist-db@latest to ensure the latest browser data is available.

Trac ticket: Core-65452.

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AI assistance: Yes
Tool(s): Claude Code
Model(s): Opus 4.7
Used for: PR created with Claude and reviewed by me.

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[github-actions]

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[github-actions]

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[Copilot]

Pull request overview

Fixes the Twenty Nineteen theme’s PostCSS configuration so both postcss-focus-within and autoprefixer run (by exporting a single module.exports), then updates Browserslist data and regenerates the compiled theme CSS to reflect current prefixing requirements.

Changes:

• Consolidate postcss.config.js to a single export and ensure autoprefixer is actually executed.
• Refresh Browserslist-related lockfile entries (e.g., baseline-browser-mapping, caniuse-lite) consistent with running npx update-browserslist-db@latest.
• Update generated CSS outputs to add/remove vendor-prefixed declarations based on the current Browserslist data.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/wp-content/themes/twentynineteen/style.css	Regenerated compiled CSS with updated autoprefixing output.
src/wp-content/themes/twentynineteen/style-rtl.css	Regenerated RTL compiled CSS with updated autoprefixing output.
src/wp-content/themes/twentynineteen/style-editor.css	Regenerated editor compiled CSS reflecting updated prefix removal.
src/wp-content/themes/twentynineteen/postcss.config.js	Combines duplicate exports and ensures both PostCSS plugins run.
src/wp-content/themes/twentynineteen/package-lock.json	Updates Browserslist data dependencies after DB refresh.

Files not reviewed (1)

• src/wp-content/themes/twentynineteen/package-lock.json: Language not supported

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