This is something that I completely overlooked during review of PR 16593, since the idea is (obviously) that the viewer-components should be usable as-is without the user needing to manually pass in any *additional* parameters.
To support this we can very easily expose the current `FilterFactory`-instance on the `PDFPageProxy`-class[1], and if needed initialize the highlight-filters when initializing the page (again limited to the viewer-components).
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