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How can I see all the "users" of a datablock? Is it possible with the Blender's UI? With Python?
For example, I'd like to know which 3 objects are the users of my material:
You can simply select one of the objects and use Shift+L > Material to select all the objects that share the same material. If the object has more than one material, it'll check for the one that's currently active.
It's a bit of a workaround. Each material has the attribute
So in order to get a list of all the objects that use a certain material, we have to loop through the objects, then through each object's material slots: