Reproduced and fixed against XWiki 17.10.9 with the demo content installed.
Before, the report page displays its own two macro calls as text where the report should be: !rn109-before.png|thumbnail!
After, the same URL reports normally: !rn109-after.png|thumbnail!
The URL used for both is /xwiki/bin/view/ReleaseNotes/Code/Report?action=report&products=XWiki&versions=8.3%&displayer=grid~ - the trailing tilde sits on displayer, which the display macro validates and falls back to its default for, so the tilde is the only difference between the two renderings.
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