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src/compiler/compile/css/Stylesheet.ts

@@ -145,6 +145,8 @@ class Declaration {
 			? this.node.value.children[0]
 			: this.node.value;
 
+		// Don't minify whitespace in custom properties, since some browsers (Chromium < 99)
+		// treat --foo: ; and --foo:; differently
 		if (first.type === 'Raw' && /^\s+$/.test(first.value)) return;
 
 		let start = first.start;