diff --git a/scripts/build.mjs b/scripts/build.mjs
index 7599d108..15d090be 100644
--- a/scripts/build.mjs
+++ b/scripts/build.mjs
@@ -358,7 +358,7 @@ async function copyFolder(srcRoot, dstRoot, filter) {
 
 function resource(relPath, content) {
     let fullPath = relPath;
-    if (!relPath.startsWith("/")) {
+    if (!path.isAbsolute(relPath)) {
         fullPath = path.join(targetDir, relPath);
     }
     const hash = contentHash(Buffer.from(content));