Strange offsets in search result highlighting

[stefan-it]

Hi,

we've seen some strange highlighting of search results in the "book" view of latest Mirador version.

Steps to reproduce:

• Go to demo site: https://mirador-dev.netlify.app/__tests__/integration/mirador/
• Import our IIIF manifest: https://api.digitale-sammlungen.de/iiif/presentation/v2/bsb00092424/manifest
• Search for the term Zimmer
• Go to search result 50, which is on page 1147

Then you'll see the following highlighting:

You can see that Zimmer is definitely not matched and there's an offset.

Then switch to "single" view. The search term is perfectly highlighted then:

/cc @cbeer

Any help would highly be appreciated :hugs:

[jbaiter]

I think this is the same bug I tried (in vain :crying_cat_face:) to fix with https://github.com/ProjectMirador/mirador/pull/3356