diff --git a/workchronicles/workchronicles.php b/workchronicles/workchronicles.php
index f15c88c..2e15165 100644
--- a/workchronicles/workchronicles.php
+++ b/workchronicles/workchronicles.php
@@ -12,50 +12,51 @@ use Shaarli\Plugin\PluginManager;
 
 function workchronicles_url(string $url): string
 {
-    echo "<pre style=\"color: lime;\">DEBUG: Checking URL {$url}</pre>";
+    if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Checking URL {$url}</pre>"; }
     $pattern = '~^https?://(?:www\.)?(?:workchronicles\.com|workchronicles\.substack\.com)/\S+~i';
     if (preg_match($pattern, $url, $m)) {
-        echo "<pre style=\"color: lime;\">DEBUG: Matched workchronicles URL {$m[0]}</pre>";
+        if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Matched workchronicles URL {$m[0]}</pre>"; }
         return $m[0];
     }
-    echo "<pre style=\"color: yellow;\">DEBUG: Not a workchronicles URL</pre>";
+    if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: yellow;\">DEBUG: Not a workchronicles URL</pre>"; }
     return '';
 }
 
 function hook_workchronicles_render_linklist(array $data): array
 {
-    echo "<pre style=\"color: lime;\">DEBUG: hook_workchronicles_render_linklist start</pre>";
+    $GLOBALS['WC_DEBUG'] = !empty($data['is_admin']) || !empty($data['is_loggedin']);
+    if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: hook_workchronicles_render_linklist start</pre>"; }
     if (empty($data['links']) || !is_array($data['links'])) {
-        echo "<pre style=\"color: yellow;\">DEBUG: Aucun lien à traiter</pre>";
+        if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: yellow;\">DEBUG: Aucun lien à traiter</pre>"; }
         return $data;
     }
 
     foreach ($data['links'] as &$link) {
         $url = $link['url'] ?? '';
-        echo "<pre style=\"color: lime;\">DEBUG: Processing link {$url}</pre>";
+        if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Processing link {$url}</pre>"; }
         $page = workchronicles_url($url);
         if ('' === $page) {
-            echo "<pre style=\"color: yellow;\">DEBUG: Skipping non-workchronicles</pre>";
+            if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: yellow;\">DEBUG: Skipping non-workchronicles</pre>"; }
             continue;
         }
 
-        echo "<pre style=\"color: lime;\">DEBUG: Fetching page content from {$page}</pre>";
+        if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Fetching page content from {$page}</pre>"; }
         list($headers, $content) = get_http_response($page);
         if (empty($content)) {
-            echo "<pre style=\"color: red;\">DEBUG: Empty content</pre>";
+            if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: red;\">DEBUG: Empty content</pre>"; }
             continue;
         }
 
-        echo "<pre style=\"color: lime;\">DEBUG: Page content length: " . strlen($content) . "</pre>";
+        if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Page content length: " . strlen($content) . "</pre>"; }
 
         $imgUrl = '';
         if (preg_match('/<meta\s+property="og:image"\s+content="([^"]+)"/i', $content, $m)) {
             $imgUrl = $m[1];
-            echo "<pre style=\"color: lime;\">DEBUG: Found og:image {$imgUrl}</pre>";
+            if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Found og:image {$imgUrl}</pre>"; }
         }
         if ('' === $imgUrl && preg_match('#<figure[^>]*>.*?<img[^>]+src="([^"]+)"#is', $content, $m2)) {
             $imgUrl = $m2[1];
-            echo "<pre style=\"color: lime;\">DEBUG: Fallback found <figure> img src {$imgUrl}</pre>";
+            if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Fallback found <figure> img src {$imgUrl}</pre>"; }
         }
 
         if ('' !== $imgUrl) {
@@ -68,25 +69,26 @@ function hook_workchronicles_render_linklist(array $data): array
             } else {
                 $link['description'] = $html;
             }
-            echo "<pre style=\"color: lime;\">DEBUG: Injected thumbnail into description</pre>";
+            if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Injected thumbnail into description</pre>"; }
         } else {
-            echo "<pre style=\"color: yellow;\">DEBUG: No image found (og:image nor <figure> img)</pre>";
+            if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: yellow;\">DEBUG: No image found (og:image nor <figure> img)</pre>"; }
         }
     }
     unset($link);
 
-    echo "<pre style=\"color: lime;\">DEBUG: hook_workchronicles_render_linklist end</pre>";
+    if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: hook_workchronicles_render_linklist end</pre>"; }
     return $data;
 }
 
 function hook_workchronicles_render_includes(array $data): array
 {
-    echo "<pre style=\"color: lime;\">DEBUG: hook_workchronicles_render_includes</pre>";
+    $GLOBALS['WC_DEBUG'] = !empty($data['is_admin']) || !empty($data['is_loggedin']);
+    if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: hook_workchronicles_render_includes</pre>"; }
     $css  = '<style>';
     $css .= '.wc-thumbnail img { border-radius: 4px; box-shadow: 0 1px 3px rgba(0,0,0,0.2); display: block; margin: 0.5em auto; }';
     $css .= '</style>';
     $data['includes'][] = $css;
-    echo "<pre style=\"color: lime;\">DEBUG: Injected CSS</pre>";
+    if (!empty($GLOBALS['WC_DEBUG'])) { echo "<pre style=\"color: lime;\">DEBUG: Injected CSS</pre>"; }
     return $data;
 }