We apologize for the instability of composr.app and appreciate your patience. We are working on the statistics addon and trying to find an optimal way to store and render data. Unfortunately, we have yet to find a solution that can handle the traffic (and therefore, tens of millions of statistical records) of composr.app. We're working hard on one.
#2931 - PDF slideshow display
https://github.com/erayakartuna/pdf-flipbook
However, it is unmaintained. I updated it a bit for a client project, only to find it fundamentally cannot support hyperlinks in PDF files.
DearFlip (https://dearflip.com/) aka dflip, is a very nice solution that does support hyperlinks, but is commercial.
pdf.js is a nice reader, but doesn't support flipbook-style reading. The above two projects actually use it internally.