Adding material to object of prefab and pressing apply doesn't update other objects!

I’m trying to follow the first tutorial in unity (roll a ball) and in this video Collecting, Scoring and Building the Game - Unity Learn
when adding a material at 8:45 to the objects by adding the material to an object and pressing apply, it updates in the video, but it’s not working on my Unity 5.6 on linux Debian, any ideas please?

I think I found out what was the problem,

In linux the hotkey Ctrl+D doesn’t work, so I had to copy/paste objects to duplicate them, and that resulted to objects not taking the material set to the prefab! I redid my work, duplicating objects using the Edit menu, and now the material applied to the prefab did get applied to all the objects!

When you copy/paste it must break the prefab link (similar to using the Break Prefab option)

To get that working, I had to delete the “pickup” object in the scene, and drag and drop the “prefab” object in the scene from the project tab. Then I could duplicate them, and hitting “apply” after having set the texutre of one of the pickup objects worked fine this time…