How versioning works

Each time the contents of a content control is saved to the server, it creates a new version of that content.

A save is initiated when you move your cursor out of a content content if you have changed the content.

The document may have been set up to prompt you for a comment about the change.

If not, the save will occur without any user intervention.

Currently, you can't do much with the old versions. For example, you can't revert a content control to a particular version, or compare the current content to a specified old version. This will come in time. What you can do is see a log of changes: