I noticed a minor issue with the ftrainworks-coupler-inserter.
The Issue:
The Coupler Inserter behaves like a standard inserter when placed next to any inventory (chests, belts, assemblers, etc.). It will grab regular items (e.g., iron plates) and attempt to move them, which can interfere with factory logistics if the coupler is placed in a crowded area.
Expected Behavior:
The Inserter should ignore all standard items and only interact with the internal dummy item used for the coupling animation.
Suggestion:
This could likely be fixed by forcing a whitelist filter on the inserter entity.
Lock the filter so players cannot change it manually.
This would ensure the inserter remains "idle" until the script triggers the coupling animation logic.

I noticed a minor issue where the internal dummy item used for animation (ftrainworks-coupler-stack) can leak into the player's inventory or the world.
Steps to reproduce:
Mining: If the Coupler Inserter is mined or deconstructed while it is active (holding the dummy item during the animation), the item ends up in the player's inventory

Since this item is missing a locale entry, it appears as Unknown key: "item-name.ftrainworks-coupler-stack"