fix markdown image render hook, handle third party image url

exampleSite/content/posts/rich-content.md

@@ -14,6 +14,16 @@ Hugo ships with several [Built-in Shortcodes](https://gohugo.io/content-manageme
 <!--more-->
 ---
 
+## Image
+
+third party image:
+
+![](https://images.unsplash.com/photo-1662141978148-2eeb2afb3837?ixlib=rb-1.2.1&ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&auto=format&fit=crop&w=772&q=80)
+
+internal image:
+
+![](images/regular.jpg)
+
 ## YouTube Privacy Enhanced Shortcode
 
 {{< youtube ZJthWmvUzzc >}}

layouts/_default/_markup/render-image.html

@@ -1,7 +1,12 @@
+{{- $url := urls.Parse .Destination -}}
+{{- if $url.Scheme -}}
+  {{/* third party image */}}
+  <img loading="lazy" src="{{ .Destination | safeURL }}" alt="{{ $.Text }}" {{ with $.Title}} title="{{ . }}" {{ end }} />
+{{- else -}}
+  {{/* internal image */}}
   {{- $img := .Page.Resources.GetMatch .Destination -}}
-{{- if and (not $img) .Page.File -}}
-  {{ $path := path.Join .Page.File.Dir .Destination }}
-  {{- $img = resources.Get $path -}}
+  {{- if not $img -}}
+    {{- $img = resources.Get .Destination -}}
   {{- end -}}
 
   {{- if $img -}}
@@ -18,3 +23,4 @@
   {{- else -}}
     {{- warnf "No image found for %s from %s" .Destination .Page.File }}
   {{- end -}}
+{{- end -}}