Anglerfish allows multiple users to open galleries at the same time, and does not warn users if someone else already has a gallery open. If a user makes a change like reordering the gallery while someone else was making edits in the same gallery, the below error message occurs. This means editors can be duplicating work without realizing it, or have work overwritten by someone else's save. It would be preferable if Anglerfish, like Ellipsis, locked files once users opened them and had a knock/takeover function.