From c4d28b9207cc53b28c5aa3d2a7ac4fa810225105 Mon Sep 17 00:00:00 2001
From: Carlos Polop <carlospolop@gmail.com>
Date: Sat, 4 Jul 2026 13:35:45 +0200
Subject: [PATCH] Support absolute sponsor image URLs

---
 theme/sponsor.js | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/theme/sponsor.js b/theme/sponsor.js
index 337740dab..6e54e2614 100644
--- a/theme/sponsor.js
+++ b/theme/sponsor.js
@@ -107,8 +107,30 @@
     return ""
   }
 
+  function resolveSponsorImageUrl(imageUrl) {
+    var value = String(imageUrl || "").trim()
+
+    if (!value) {
+      return ""
+    }
+
+    if (/^https:\/\//i.test(value)) {
+      return value
+    }
+
+    if (/^\/\//.test(value)) {
+      return "https:" + value
+    }
+
+    if (value.charAt(0) === "/") {
+      return new URL(value, window.location.origin).href
+    }
+
+    return new URL(value, document.baseURI || window.location.href).href
+  }
+
   function setLegacySponsorContent(sponsor, container, nodes) {
-    nodes.img.src = sponsor.image_url
+    nodes.img.src = resolveSponsorImageUrl(sponsor.image_url)
     nodes.img.alt = sponsor.name
     nodes.title.textContent = sponsor.name
     nodes.description.innerHTML = sponsor.description