"Assembly-Worker" not shown in list of creature types
When playing a card that asks you to choose a creature type, e.g. Bloodline Pretender, Herald's Horn, or Unclaimed Territory, typing in "Assembly-Worker" shows an empty list. typing in just "a" and scrolling down shows the list goes "Artificer">"Assassin">"Atog">"Aurochs".
This is relevant because there are two creatures in Arena that have the Assembly-Worker type: Self-Assembler and Mishra's Self-Replicator.