static/js/instantpage: Add custom prefetch

1 files changed, 18 insertions, 5 deletions

diff --git a/assets/js/index.js b/assets/js/index.js
index e0e0436..f6c1686 100644
--- a/assets/js/index.js
+++ b/assets/js/index.js
@@ -165,9 +165,18 @@
     }
 })();
 (function() {
+    function fetch(url, method, callback) {
+        const http = new XMLHttpRequest();
+        http.onreadystatechange = function() {
+            if (http.readyState === 4 && http.status === 200) {
+                if (callback) callback(http);
+            }
+        };
+        http.open(method, url);
+        http.send();
+        return http;
+    }
     self.addEventListener("DOMContentLoaded", function() {
-        let mouseoverTimer;
-        let lastTouchTimestamp;
         const prefetches = new Set();
         const prefetchElement = document.createElement("link");
         const isSupported = prefetchElement.relList && prefetchElement.relList.supports && prefetchElement.relList.supports("prefetch") && window.IntersectionObserver && "isIntersecting" in IntersectionObserverEntry.prototype;
@@ -175,6 +184,8 @@
         const allowExternalLinks = "instantAllowExternalLinks" in document.body.dataset;
         const useWhitelist = "instantWhitelist" in document.body.dataset;
         const mousedownShortcut = "instantMousedownShortcut" in document.body.dataset;
+        let mouseoverTimer;
+        let lastTouchTimestamp;
         let delayOnHover = 65;
         let useMousedown = false;
         let useMousedownOnly = false;
@@ -354,10 +365,12 @@
                 return;
             }
             const prefetcher = document.createElement("link");
-            prefetcher.rel = "prefetch";
+            prefetcher.rel = "custom-prefetch";
             prefetcher.href = url;
-            document.head.appendChild(prefetcher);
-            prefetches.add(url);
+            fetch(url, "GET", function() {
+                document.head.appendChild(prefetcher);
+                prefetches.add(url);
+            });
         }
     });
 })();