diff --git a/eleventy.config.js b/eleventy.config.js
index 4d355ad..487f799 100644
--- a/eleventy.config.js
+++ b/eleventy.config.js
@@ -455,6 +455,7 @@ export default function (eleventyConfig) {
 
   eleventyConfig.addTransform("og-fix", function (content, outputPath) {
     if (!outputPath || !outputPath.endsWith(".html")) return content;
+    if (!content.includes("__OG_IMAGE_PLACEHOLDER__")) return content;
 
     // Derive correct page URL and OG slug from outputPath (immune to race condition)
     // Content pages match: .../type/slug/index.html
@@ -688,9 +689,9 @@ export default function (eleventyConfig) {
       try {
         return await minify(content, {
           collapseWhitespace: true,
+          conservativeCollapse: true,
           removeComments: true,
           html5: true,
-          decodeEntities: true,
           minifyCSS: false,
           minifyJS: false,
         });
@@ -828,23 +829,26 @@ export default function (eleventyConfig) {
   });
 
   // Clean excerpt for OpenGraph - strips HTML, decodes entities, removes extra whitespace
+  // Memoized: same post content is processed once per post page + once per listing page card
+  const _ogDescCache = new Map();
+  eleventyConfig.on("eleventy.before", () => { _ogDescCache.clear(); });
   eleventyConfig.addFilter("ogDescription", (content, len = 200) => {
     if (!content) return "";
-    // Strip HTML tags
+    const key = `${len}:${content.length}:${content.slice(0, 64)}`;
+    const cached = _ogDescCache.get(key);
+    if (cached !== undefined) return cached;
     let text = content.replace(/<[^>]+>/g, ' ');
-    // Decode common HTML entities
     text = text.replace(/&amp;/g, '&')
                .replace(/&lt;/g, '<')
                .replace(/&gt;/g, '>')
                .replace(/&quot;/g, '"')
                .replace(/&#39;/g, "'")
                .replace(/&nbsp;/g, ' ');
-    // Remove extra whitespace
     text = text.replace(/\s+/g, ' ').trim();
-    // Truncate
     if (text.length > len) {
       text = text.slice(0, len).trim() + "...";
     }
+    _ogDescCache.set(key, text);
     return text;
   });