When the user tries to import a page display template that contains a Fragment from the Global Site, the fragment does not get imported.
Based on the PTR that was opened, the correct behavior should be that when the Fragment is being imported, the Local and Global Site should be referenced when searching for the fragment.
Steps to reproduce
1. Start with a clean bundle of Master
2. Navigate to the Global site.
3. Navigate to fragments page: Design -> Fragments
4. Create a new collection: 'Test Collection'
5. Create a new fragment 'Test Fragment' - see attachment 'entries-20211012103408709.zip'
6. Navigate to the default (Liferay DXP) site
7. Navigate to the Page Templates page: Design -> Page Templates -> (tab) Page Templates
8. Create a new collection: 'Test Collection'
9. Create a new Content Page Template: 'Test Page Template' (use the Blank/default Master page)
10. Place an instance of the 'Test Fragment' by dragging it from the right-hand fragments menu onto the page. The fragment shows as expected.
11. Publish the page.
12. Export the page template: Click on the page template action menu and choose 'Export' - see attachment 'page-template-test-page-template-202110121043.zip'
13. Navigate to the sites menu: Control Panel -> Sites
14. Create a new site, 'Test Site' using the default settings.
15. Navigate to 'Test Site'.
16. Navigate to Page Templates page: Design -> Page Templates -> (tab) Page Templates
17. Attempt to import the page template: Options menu (control-bar) -> Import -> [Test Page Template zip file]
Page template imports without errors, and includes the 'Test Fragment'.
Page imports with warning: 'Fragment with key test-fragment-0 was ignored because it does not exist'. Open the page template, and it is blank. Look at the Fragments panel on the right-hand side and observe that the 'Test Fragment' is still available and can be added to the page.