while working on the outliner (specifically D992: Outliner: DragDrop materials to groups (to assign material to every group member)), I came across an inconsistency when linking of materials to objects. atm we have the following behaviour:
(1) CTRL+L > Materials:
assigns/overwrites the material to the first material slot
(2) drag n drop from/to the outliner:
create new material slot and assign to this
(3) drag n drop from the outliner to 3DView:
assigns/overwrites the material to the first material slot
So this patch will make it so (2) acts as (1) and (3).
I really dont see the reasoning to not have this consistent (even though the original commit message explictly mentions this: "Adds the material at materials + 1 unlike the DnD view3d one which replaces the first one"...)
had a quick about this with ideasman42 in IRC and at first glance this was his answer there...
<lichtwerk> while we are at it: what do you think about the consistency in dnd material>>object (see https://developer.blender.org/D992)?
<ideasman42> probably these should both work the same way
<ideasman42> I expect this is just sloppy design