Do I need to run the Nested Pages Migrator?

Starting with XWiki 7.2, XWiki supports the concept of Nested Pages.

There's an extension available called the Nested Pages Migrator to help you convert Terminal pages (i.e. pages that cannot have children) into Nested Pages.

You should check the Nested Pages migration guide to know more.

As a summary, here's what would happen to the breadcrumbs after you upgrade:

If you had this before the upgrade

• URL: /xwiki/bin/view/A/B
• Breadcrumb: Home / X / Y / B

Then after the upgrade (without any migration) you'll have:

• URL: /xwiki/bin/view/A/B
• Breadcrumb: Home / A / B

So you "loose" the parent-child hierarchy. Actually the information is not lost, but the new breadcrumb doesn't use it. The new breadcrumb uses by default the page location (what you have in the URL). So you have 3 options:

1. You don't care about the old parent-child hierarchy. In this case you
   don't need to do anything.
2. You want to keep using the parent-child hierarchy. In this case you
   need to read about hierarchyMode configuration in the Nested Pages migration guide
3. You want to convert / migrate the parent-child hierarchy to the
   Nested-Pages hierarchy. In this case you either use the Nested Pages
   Migrator, which automates this for you, or you do it manually my moving
   pages around (e.g. in the example above you would move page B from A to X/Y so that its location becomes X/Y/B).