Encryptpad not installing because a missing package - botan2

encryptpad is a custom build using AUR build script → AUR (en) - encryptpad

botan2 is not yet in stable → Packages

So you have to wait until next stable snap - or switch to testing branch - you decide.

EDIT:

Package build as expected on unstable branch.

 $ pamac build encryptpad
[...]
==> Creating package "encryptpad"...
  -> Generating .PKGINFO file...
  -> Generating .BUILDINFO file...
  -> Generating .MTREE file...
  -> Compressing package...
==> Leaving fakeroot environment.
==> Finished making: encryptpad 0.5.0.2-11 (søn 21 maj 2023 14:53:15 CEST)
==> Cleaning up...