1. v1
   1. User opens "Compare"-view
   2. User selects file to compare current workbook with
      1. current workbook = wb
      2. compared workbook = wbcomp
   3. Load wbcomp's content.xml and make a diff with wb's content.xml
   4. regexp through diff result
      1. new/deleted sheets
      2. new/deleted topics
      3. check if deleted sheet/topic has been added elsewhere -> move
      4. changes within <title> tag -> changed text
   5. Display list of sheets with added/removed/moved/renamed branches
      1. Hover shows added, highlights removed/moved/renamed
   6. Click on icon next to the branches in the list adds/removes/moves/renames that branch according to the diff
   7. Finish comparison with click on close/finish-button
2. v2
   1. Images?
   2. Preview added sheets
   3. Other changes in the .xmind-file
      1. Eg. styles