When joining, If both objects are of the same instance, their layers are merged respectively.
But if they are not of the same instance, what behaviour do you expect?
Not sure if I should differentiate default name (Mesh 0,1,2 or Layer 0 1 2) vs custom names.
Edit: For now I decide on: Merge layers with same custom names, do not merge default names (except for instance meshes)
Would the layers with the same custom name merge even if the meshes have different names?
I read your question earlier and tried to think what I would prefer - it’s tricky, in some cases I would prefer one option, in others, something different.
If we have the rule: “same custom name layers merge” then at least we have control, and can rename layers if necessary to affect the behaviour.
Yes, if it starts with “Layer” it won’t merge it.
The object name won’t be used, only the layer name.
Layers with the same name inside a single mesh won’t be merged either.
sidestepping this issue, can we get a way to merge multiple layers via a check mark like the object join? at times there are multiple layers I try to join that are far apart in the list and doing so takes a long time (could also be useful for checking multiple layers and setting values on all of them for example)