Autocomplete doesn‘t work

Beschreibung: Either there appears a box without entries or nothing if I enter a word in the custom search field of a tracker, I.e. https://wiki-to-yes.org/Lexikon if I enter something there appears a box the spin showing somthing is working turns around but nothing happens. No results where shown. The video "search in tracker and top bar.mov" (https://www.dropbox.com/scl/fi/hau69wmc1k1n6z8oql2bb/search-in-tracker-and-top-bar.mov?rlkey=9p6a0wwx8a9d8b2uq3xqcg3zc&st=u3g4fk23&dl=0) gives an example. On https://wiki-to-yes.org/Interventionenfinder no proposal if I ender something thoufh the trackeritem exists. If I enter "app" nothing if I endter "abbruch" no proposals though the item exists. If I click the search button at least the item is found. See video https://www.dropbox.com/scl/fi/8fsjphvopi3c7z5nhiawa/Search-Abbruch.mov?rlkey=f6igexnxe8rgxmmrb9657xng8&st=yo9y98id&dl=0
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