Additionally, accessing the codex... I believe the term is soft-locks you, as it does not seem to respond to any keyboard commands or show any button to press to go back (go up a level in the menu list). Which can be seen here:
I apologize for the large images, as I do not see a way to edit the size in the itch.io app's access to this forum.
My PC specs are the following (At least according to Windows' "This PC" properties, if more information is needed, please let me know.):
Windows 10 (update KB4569751) x64
AMD Ryzen 3 1300X Quad Processor 3.5GHz
20GB of installed memory (RAM)