On Windows XP, I do not have the Filter control (above the Navigator), nor the other buttons - still yesterday.
How can I get them back ?
Below: the part (on OS X) that I do not have under Windows:
Funny: while I was searching a screen shot for another conversation, I saw the missing stuff, on a cimpiler error screen shot !
No idea
I’ve never seen them disappear
Strange things happens here.
MacBook Pro 2011-11
OS X 10.8.5
VirtualBox 4.3.8 / Window XP SP III
This version of Windows is haunted 
I do not believe in that, but sometimes, I wonder !
On the other hand, I have it since 2003 (first in a true PC laptop, then in VirtualBox)
Damn! I just found a similar, if not the same, problem. I had a Desktop app open in the IDE and selected “Hide the Toolbar” from the View menu. Then I closed Xojo. Now, whenever I open Xojo, the toolbar space is there but has no buttons in it until I select “Show Toolbar” from the View menu.
I’m running 2013r4.1 on 64-bit Windows 7.
I just filed a bug report on it: <https://xojo.com/issue/32500>
I did some more testing and found that this problem does not always crop up, but when it does it is persistent. In my report I added a way to resolve it on the local level but you need to be comfortable editing your machine’s registry (Windows obviously).