perf: don't load duplicate styles for link tags with matching hrefs

measuredco · Apr 16, 2024 · ad6452f · ad6452f
1 parent d298f1b
commit ad6452f
Showing 1 changed file with 13 additions and 1 deletion.
diff --git a/src/AutoFrameComponent.tsx b/src/AutoFrameComponent.tsx
@@ -205,9 +205,21 @@ const CopyHostStyles = ({
     const parentDocument = win!.parent.document;
 
     const collectedStyles = collectStyles(parentDocument);
+    const hrefs: string[] = [];
 
     Promise.all(
-      collectedStyles.map(async (styleNode) => {
+      collectedStyles.map(async (styleNode, i) => {
+        if (styleNode.nodeName === "LINK") {
+          const linkHref = (styleNode as HTMLLinkElement).href;
+
+          // Don't process link elements with identical hrefs more than once
+          if (hrefs.indexOf(linkHref) > -1) {
+            return;
+          }
+
+          hrefs.push(linkHref);
+        }
+
         const mirror = await mirrorEl(styleNode);
 
         if (!mirror) return;