#171

backend/app/models/tag.rb

@@ -136,6 +136,7 @@ class Tag < ApplicationRecord
     tn = tn.canonical if tn.canonical_id?
 
     Tag.find_undiscard_or_create_by!(tag_name_id: tn.id) do |t|
+      t.version_no = TagVersion.where(tag_id: t.id).order(version_no: :desc).first || 1
       t.category = category
     end
   rescue ActiveRecord::RecordNotUnique