SASS + CSS Module cause issues on production build, part of styles are missing to be exact.
gatsby new test to create a new project.gatsby-plugin-sass and add it to gatsby-config.js.styles.module.scss under src/components/Header with a simple .red { color: red; } within.src/components/Header/index.js, import styles from './styles.module.scss, and use it anywhere you want.gatsby build then serve publicStyles from layouts is missing from generated inline styles within <style id="gatsby-inlined-css">.
e.g. Styles for <body> should exist.
It's gone.
1.9.2311.1.458.9.4macOS High SierraReplacing gatsby-plugin-sass with gatsby-plugin-postcss-sass seems works.
There is an issue with a recent update of gatsby-plugin-sass the plugin author is looking into it A temporary solution is to specify the version of gatsby-plugin-sass #4457
Fixed in #4495.
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There is an issue with a recent update of gatsby-plugin-sass the plugin author is looking into it A temporary solution is to specify the version of gatsby-plugin-sass #4457