claws-mail upstream made a release without nonfree pilot-link dependency which is a suite of tools for connecting to PalmOS handheld devices. This means Parabola's claws-mail-libre isn't needed anymore since version 3.9.2-4 and it will be removed from repos.
You should install the claws-mail package manually using regular pacman methods. Accept the claws-mail-libre removal and that's it.