fix(legacy): don't lower CSS if legacy chunks are not generated (vitejs#20392)

sapphi-red · web-flow · commit d2c81f7c1303 · 2025-07-11T14:13:40.000+02:00
diff --git a/packages/plugin-legacy/src/index.ts b/packages/plugin-legacy/src/index.ts
@@ -209,7 +209,7 @@ function viteLegacyPlugin(options: Options = {}): Plugin[] {
           config.build = {}
         }
 
-        if (!config.build.cssTarget) {
+        if (genLegacy && !config.build.cssTarget) {
           // Hint for esbuild that we are targeting legacy browsers when minifying CSS.
           // Full CSS compat table available at https://github.com/evanw/esbuild/blob/78e04680228cf989bdd7d471e02bbc2c8d345dc9/internal/compat/css_table.go
           // But note that only the `HexRGBA` feature affects the minify outcome.

Original file line number	Diff line number	Diff line change
`@@ -209,7 +209,7 @@ function viteLegacyPlugin(options: Options = {}): Plugin[] {`
`209`	`209`	`config.build = {}`
`210`	`210`	`}`
`211`	`211`
`212`		`- if (!config.build.cssTarget) {`
	`212`	`+ if (genLegacy && !config.build.cssTarget) {`
`213`	`213`	`// Hint for esbuild that we are targeting legacy browsers when minifying CSS.`
`214`	`214`	`// Full CSS compat table available at https://github.com/evanw/esbuild/blob/78e04680228cf989bdd7d471e02bbc2c8d345dc9/internal/compat/css_table.go`
`215`	`215`	// But note that only the `HexRGBA` feature affects the minify outcome.