Content creation is an iterative process. Authoring with efficiency requires being able to see what has changed from one iteration to another. Viewing one page version and then the other is inefficient and prone to error. An author wants to be able to easily compare the current page side-by-side with another version.
The page diff feature allows for the convenient side-by-side comparison of two pages with their differences highlighted.
The user must have the Modify/Create/Delete permission on the node
/content/versionhistory in order to use the feature.
See Developing and Page Diff for more technical details on this feature.
The side-by-side diff can compare:
See the respective topics on how to start the diff within those contexts.
Regardless of the content being compared, the presentation of the diff remains the same.
For example if comparing versions, the current version is displayed on the left and the previous version is displayed on the right.
The source of both pages is clearly displayed in the header bar at the top of the browser window.
The diff detects changes at the component and HTML level. Items that have been changed are highlighted with different colors.
When comparing language copies, highlighting is deactivated since in a translation everything changes and highlighting would be of no benefit.
In order to focus on particular content, you can click on the full screen icon for either “side” of the side-by-side diff to enlarge it to the full browser window.
The selected side will fill the entire window, but the bar will remain at the top allowing you to switch between the two pages.
If the browser width can not accommodate both page names in full screen view, only the name of the page being displayed will be shown and the other will be available behind ellipsis.
You can also choose to close the full screen view by clicking the exit full screen icon.
You can exit the side-by-side diff at any time by clicking the Close button in the header.
There are some situations in which the page diff may not detect a difference as expected.
Versions can not be compared to each other. Only the current version can be compared with other versions of the page. The current version is always the version that is highlighted with changes.
For more details about the operation of the page diff mechanism as well as limitations which can affect page diff, please see the developer documentation of this feature.