Object editor loads too slowly when there are a large number of xobjects/xproperties to load

To reproduce:

• Use this snippet () to create a page with 100 XWiki.XWikiComments xobjects
• Notice that the page load speed is acceptable
• Try to edit in the object editor. If your use is using the WYSIWYG editor it should take more than 10s (about 7-8s with the text editor).

Idea:

• Display all the xobject but only display the xproperties when expanding the xobjects.

Note that this issue is currently making it impossible to edit some extensions pages on e.x.o since they take more than 100s to display and we have a CloudFlare timeout appearing at 100s.