The Include+ and the Excerpt Include+ macros are extended versions of the native Include Page and Excerpt Include macros. In past versions, these macros could also appear to work in spaces that aren't using Scroll Versions or Scroll Translations, referred to as unmanaged spaces. However, these macros are considered to be third-party by Confluence, meaning they cannot be used without the Scroll Versions or Translations apps or on Confluence Cloud.
Include+ and Excerpt Include+ macros cannot be migrated and should be replaced before migrating spaces to Confluence Cloud.
It is thus recommended not to use Include+ or Excerpt Include plus in spaces that don't use any Scroll Versions or Scroll Translations features.
Find and Fix Affected Pages
To check whether an unmanaged space is using Include+ or Excerpt Include+ macros, navigate to Space Tools > Scroll Add-ons > Fix Include+ macros.
The table lists all pages in the current spaces that have either Include+ or Excerpt Include+ macros on them. To convert the macros to their native counterparts, click Fix macros.
Only macros that include a precisely defined page or excerpt are fixed by this automated conversion tool. Pages for which this isn't possible will remain in the list and need to be fixed manually.
Using the REST API, the Include Macro Resource provides programmatic access to the space-wide tools listed in the Space Tools section above. Additionally, the REST API provides an instance-wide search for affected spaces, which returns a table containing the space keys of affected spaces and a link to the Fix Include+ macros UI of the space at hand.