[PROBLEM] Toolbar

Hello! I have this problem with the toolbar:
When i create a new object in the viewport such as an UV sphere, cube or, in this case, a bolt from the bolt factory add-on, i go to the toolbar to set the different options of the object (eg: #of rings of an UV sphere) but when i try to do that, all that part of the toolbar is grey, it’s like i’m unable to edit any option box of it.
Like I said, i’m having this problem with each mesh I create in the viewport. I don’t know why is this happening, so i came to you guys.
Hope to read some response here.
Here is an image:

Hi, another user had the same problem and solve it.


Cheers, mib.

I still haven’t found the exact cause, just that something in userpref.blend got messed up. This sounds like the third case (another here maybe) so maybe there is a bug lurking?

Aha! I can duplicate the issue by turning off global undo. The link Storrboy posted clued me in.

A quick search found this:

Not a bug. Just another Blender quirk / hidden pitfall. A feature depending on another seemingly unrelated feature.

How unusual (not).