In Photoshop CC I have no 'Extensions' menu under Window. I get Arrange > Workspace > 3D then everything else. I've searched and heard of it being greyed out but not missing entirely.
Extensions manager has been used properly to install my extensions, and I've manually checked everything is where it should be. I ran the manager as admin.
This is on a PC, W7 Pro 64BIT, CC is all up-to-date. PS version 14.2.1 (14.2.1 20140207.r.570 2014/02/07:23:00:00) x64
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