One more thing. The app seems to be compiled for macOS >= 26.0 according to Info...

johndoe0815 10 months ago | parent | context | favorite | on: PageFlow – The ultra-minimalist, native macOS PDF ...

One more thing. The app seems to be compiled for macOS >= 26.0 according to Info.plist, but your web page indicates "Requires macOS 12 or higher". So I think there's something wrong with your build settings.