[mod] engine lemmy: increase thumbnail quality to align with theme

searx/engines/lemmy.py

@@ -129,7 +129,7 @@ def _get_posts(json):
 
         img_src = None
         if result['post'].get('thumbnail_url'):
-            img_src = result['post']['thumbnail_url'] + '?format=webp&thumbnail=128'
+            img_src = result['post']['thumbnail_url'] + '?format=webp&thumbnail=208'
 
         metadata = (
             f"▲ {result['counts']['upvotes']} ▼ {result['counts']['downvotes']}"