To save changes in MockFlow, the user needs to click the 'Save' button from the top menu. or the 'Save Changes' button that automatically appears in the top-right corner of the screen.
However in the background, MockFlow automatically saves user changes by creating auto-revisions, so even when the user forgets/unable to 'save' the changes, the unsaved work can always be recovered by previewing and restoring auto-revisions from the 'Revision History' located in the top menu.
1After opening the page with lost changes, From the project menu click revision history.
2Select the revision.
3Preview the changes.
4If ok, Restore the page to that revision.