backend/app/models/post.rb

@@ -22,6 +22,7 @@ class Post < ApplicationRecord
     bytes = upload.read
     blob = Timeout.timeout(THUMBNAIL_PROCESS_TIMEOUT) do
       image = image_for_thumbnail_upload(bytes, content_type:)
+      image.auto_orient
       image.resize '180x180'
       image.format 'jpg'
       image.to_blob