Seems like the ZoomSelected acts differently on Blocks vs other objects.
The same geometry when turned into a block and ZoomSelected-ed leaves much bigger margin in the view around it vs. non-block ones.
(sample file: ZoomSelTest.3dm (648.8 KB) )
Is this a bug? Are currently processing a lot of block objects libraries and all of their preview/thumbnail images are zoomed out more than they should be.