diff --git a/app/Models/Media.php b/app/Models/Media.php
index bc7fe75..a18a21d 100644
--- a/app/Models/Media.php
+++ b/app/Models/Media.php
@@ -694,11 +694,13 @@ class Media extends Model
                 }
                 $im = $im->deconstructImages();
             }
+            $im->setImageFormat(MediaExtension::gif);
             $storage->put(
                 $this->preview_relative_path,
                 $im->getImagesBlob()
             );
         } else {
+            $im->setImageFormat(\pathinfo($this->preview_relative_path, \PATHINFO_EXTENSION));
             if ($this->largeur >= $format->largeur || $this->hauteur >= $format->hauteur || $this->largeur == "") {
                 $im->thumbnailImage($format->largeur, $format->hauteur, true);
             }