1. Hover your cursor over the trigger area on the left side of the screen to open the left sidebar and click the thumbtack icon to pin the sidebar open.
2. Click on ‘Drafts’
3. Right-click on the old draft you want to compare.
4. Select ‘Compare to current version’
5. In the ‘Changes’ menu in the top-right, choose how you want to see the differences between the two drafts.