All your previous changes from Email & Query Studio saved!
When an email is updated in Salesforce Marketing Cloud (SFMC, formerly exacttarget), the previous versions are not stored and the old version is lost forever. This chrome add-on aims at capturing all previous version and allows SFMC developers to view, download or revert back to any of the previous versions.
The network requests to marketingcloudapps.com & exacttarget.com are interpreted to capture the PUT method body and are stored in local storage - which is then used for viewing, downloading or reverting the email content back to previous version.