Steps to reproduce:
Open a PDF using the in-browser viewer.
Use command-f to begin a search.
Type something in the search bar.
No search results (web pages work fine).
Searches should work the same in PDFs as they do in webpages.
Orion, OS version; hardware type:
Orion: Version 0.99.113.2-beta (WebKit 613.1.12)
MacOS Monterey 12.3.1
M1 MacBook Pro