Ignore missing attachments

app/models/account/data_transfer/action_text_rich_text_record_set.rb

@@ -57,11 +57,17 @@ class Account::DataTransfer::ActionTextRichTextRecordSet < Account::DataTransfer
 
       content.send(:attachment_nodes).each do |node|
         sgid = SignedGlobalID.parse(node["sgid"], for: ActionText::Attachable::LOCATOR_NAME)
-        record = sgid&.find
-        next if record&.account_id != account.id
 
-        node["gid"] = record.to_global_id.to_s
-        node.remove_attribute("sgid")
+        record = begin
+          sgid&.find
+        rescue ActiveRecord::RecordNotFound
+          nil
+        end
+
+        if record&.account_id == account.id
+          node["gid"] = record.to_global_id.to_s
+          node.remove_attribute("sgid")
+        end
       end
 
       content.fragment.source.to_html
@@ -74,11 +80,12 @@ class Account::DataTransfer::ActionTextRichTextRecordSet < Account::DataTransfer
 
       fragment.css("action-text-attachment[gid]").each do |node|
         gid = GlobalID.parse(node["gid"])
-        next unless gid
 
-        record = gid.find
-        node["sgid"] = record.attachable_sgid
-        node.remove_attribute("gid")
+        if gid
+          record = gid.find
+          node["sgid"] = record.attachable_sgid
+          node.remove_attribute("gid")
+        end
       end
 
       fragment.to_html

test/models/account/export_test.rb

@@ -59,4 +59,21 @@ class Account::ExportTest < ActiveSupport::TestCase
       assert entry, "Expected blob file in zip"
     end
   end
+
+  test "build succeeds when rich text references missing blob" do
+    blob = ActiveStorage::Blob.create_and_upload!(
+      io: file_fixture("moon.jpg").open,
+      filename: "moon.jpg",
+      content_type: "image/jpeg"
+    )
+    card = cards(:logo)
+    card.update!(description: "<action-text-attachment sgid=\"#{blob.attachable_sgid}\"></action-text-attachment>")
+    ActiveStorage::Blob.where(id: blob.id).delete_all
+
+    export = Account::Export.create!(account: Current.account, user: users(:david))
+
+    export.build
+
+    assert export.completed?
+  end
 end