In XWiki, everything is historized and saved under Version Control.

History View

When looking at a page you can see who last modified it and the time the change was performed:

You can see the versions of a page by looking at the "History" tab at the bottom. For example, on the following screenshot the last version is 8.1 and has been modified by "Administrator".

"History" as it appears using the Flamingo Skin

The page version consists of two numbers, separated by a dot: <Major>.<Minor>. The XWiki versioning system allows the distinction between major and minor edits. When editing a page, the user has the option to decide whether his/her edit brings major or minor changes to the page. Saving a major version will increase the first component and reset the second to "1", while a minor version will just increase the second component.

Clicking on the "History" button when viewing a page displays all the versions that were previously saved:

Besides listing the page versions, the history page can be used to perform other actions as well:

• View a previous version of the page
• Compare any two versions
• Set an older version as the current version (rollback); available only if the user has edit rights on the page
• Delete a version completely from the history (useful for removing spam, for example); available only if the user has administration rights
• Delete an entire version range from the history; also available only if the user has administration rights

By default, minor edits do not appear in the page history. The option "Show minor edits" will list all the versions, including minor ones. To know more about minor and major edits, have a look at the Page Editing documentation page.

The history also displays, on the first line, the standard version of the page, as contained by the installed Extension (if the page comes from an extension), in that installed version. This can be different from the first version of the page (v1.1) since the page could have had edits before an extension was installed that modified the page or if the extension has been upgraded.

XWiki 14.10.7+, 15.2+ When viewing a previous version of the page, the content of that previous version is rendered in a special "restricted" mode that prevents the execution of script macros and other dangerous macros to avoid that old code that might have contained problems is executed even though it has been fixed in the current version of the page. This may lead to errors being displayed and other differences in behavior to the current version.

Comparing Versions

The comparison between two page versions can be done either on the raw content or (since XWiki 11.6RC1) on the rendered content.

In order to compare 2 versions you need to select one of the radio buttons corresponding to the version from which you want to start the comparison. These are the buttons located in the "From" column. You will then need to select the button corresponding to the version you want to compare the previously selected version against. These buttons are located in the "To" column. You may choose to include minor edits in the comparison. After selecting the 2 versions you wish to compare you will need to click on "Compare selected versions".

Clicking on either one of the 2 compared version numbers (shown on the header) will display that version of the page.

Raw Changes

The raw changes between two page versions highlights the differences between page properties (title, content, parent, syntax, etc.), attachments, objects and class properties. Depending on the changes you have made you will get a result similar to this:

"Changes for page" as they appear using the Flamingo Skin 

Note that the comparison starts with a Summary that groups the changes in 4 categories: Page Properties, Attachments, Objects and Class Properties. A category is displayed only if there are related changes. Except for 'Page properties', the rest of the categories can be expanded to see which items have been added, deleted or modified. Each item provides a link to the details that are listed below the Summary.

The comparison details lists all the items (page properties, attachments, objects, class properties) that have been added, deleted or modified. For each item you can see what properties have been modified and the exact modifications. For text attachments you can even see the changes made to the attachment content between two versions of the attachment. The changes made to the object properties of type Password and Email are obfuscated for privacy reasons.

Rendered Changes

You can view how the page has changed visually from one version to another. The changes are computed on the rendered page content. The parts of the content that have not been modified are hidden by default but you can click on each ellipsis to view more context or you can use the "Show context" button to view the entire page content.

XWiki 14.10.7+, 15.2+ Similar to the behavior when viewing a previous version of a page, the content of previous versions is executed in a "restricted" mode that might lead to errors and other differences.

Show next/previous changes

You can change the versions directly while comparing two page versions, using the arrows depicted in the image below.

By clicking on the leftmost arrow, you will see the previous change made before the "From" version. For example, if the current comparison is between revision 4.1 and 6.1, clicking the left arrow would compare revisions 3.1 and 4.1 (assuming there are no minor versions). Similarly, the next change will be displayed by clicking the rightmost arrow (e.g. clicking the right arrow while comparing revision 3.1 and 5.1 will lead to 5.1 and 6.1 comparison). You can also use the arrows around a version to increase or decrease the associated version number.

Viewing Previous Versions

By clicking on a version from the Version column of a page's History tab you will be able to view that page's content, as it was in the selected version:

In this view, most actions on the page will actually affect the latest version of the page. However, the following actions (under the "More Actions" menu) will target the current version of the page you are viewing:

• Export
• Print Preview
• View Source

Blame View

When viewing the source of a page (by going to More Actions > View Source on a page), you can enable the blame view by clicking on Show last authors button. In this mode, each line of the page's content is annotated with the last author that modified it and the revision in which this modification was introduced. The blame view also works when viewing the source of a page revision (other than the latest one) so it can be accessed at any point in the history of a page.

Hovering the avatar and the revision number will display the author's name and the date and time when the line was changed. Multiple lines can be grouped to express the fact that they were all modified within the same revision (by the same author and at the same time).

Clicking on the revision number will display the changes view, with all the modifications performed in that particular change by its author.

At this point, if you still have not found the change you were looking for related to a particular line of content, you could continue the search by clicking on the parent (left) version, opening the blame view for it and repeating the cycle. This way you can drill down the history and focus on the content and find out, for example, when exactly was a line added, in which context and by whom.