collision_mask ={player-level, ...} makes entity unplaceabel

[rude_grass]

I created a mod, that adds an entity that is placeable on water and contains:
oil_rig.collision_mask = {'ground-tile', 'object-layer', "player-layer"}
the addition of "player-layer" to the collision mask lead to me receiving multiple bug reports from users, that the entity is not placeable anymore. I tested the mod with the latest stable and experimental versions, and did not run in a similar issue.
Now i am at a complete loss: I can't reproduce the issue and do not know what could be causing it. Does anybody have an idea how 'player-level' could interfere with the entity being placeable?

[eradicator]

All water tiles collide with the player-layer because the player can't swim. Not sure how you manage to not reproduce that from the description. Unless you have mods that enable swimming and thus probably remove the player-layer from water tiles...