After update, grub doesn't find windows install

[papajoke]

[Stable Update] 2021-03-08- Kernels, Plasma 5.21.2, Haskell, Kodi, Grub, KDE-Dev

Through a recent patch, os-prober seems to have been disabled by default. See here for details: https://gitlab.manjaro.org/packages/core/grub/-/commit/991784fbecb814a14651e1ccbd0dd6b08de2a129 I had the same issue and could resolve it by manually adding the line GRUB_DISABLE_OS_PROBER=false to /etc/default/grub.