I'd be so happy with a 24,000 page PDF, cause then at least you know where too look, and you can the search tool. I programme Siemens hardware and the docs I need are spread out over many tens of PDFs (of 100-1500 pages). I haven't found a proper tool than can let me search and view all this documentation properly. Best I found is ripgrep with some PDF extension to search which document I need, and then use SumatraPDF for finding the right page... ughh