From https://en.wikipedia.org/wiki/Special:Search?search=ugly&fulltext=1&cirrusUserTesting=recall_sidebar_results&searchToken=362e1qz8z5cc9qtw1y48rb7gj it appears that Cross-wiki search tries to read the (history of) annotations on commons. It finds strings like " ugly stitching error" here: https://en.wikipedia.org/w/index.php?title=Special:Search&profile=images&search=ugly&fulltext=1
Topic on Talk:Cross-wiki Search Result Improvements
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Hi @Mduvekot, the testing URL that you're using in your sample is currently awaiting a new code update to not display the commons / multimedia results in the sister project snippets on English Wikipedia.