libidn2 was already updated last time. With libidn2 2.1.1-2 libidn2.so provision got added to help prevent partial upgrades breaking pacman. It would be great to know on which stage you got this breakage on your end.
I’ve reverted a commit which introduced the breakage, however there is still no proper fix from upstream. No worries, this update won’t break your system in that regard. I only want to point to an issue, which is not yet properly fixed by upstream.