This task is a todo list for missing face set operators. [s] means operator works on either a user-picked face set or all of them.
# Face Set[s] `<->` Vertex Groups
# Face Set[s] `<->` Face Maps
# Face Set[s] `->` UV Seams
# Face Set[s] `->` Mask
# Make Disconnected Face Sets Unique
# Separate By Face Sets
# Face Set[s] `<->` Material Slots
# Face Maps `<->` Face Sets