It's not The GIMP's job to do that. Simply configure your window
manager to keep the GIMP's toolbox always on top.

Hmmm...  I assume that the problem is more annoying with Windows than
with most other operating systems.  Also, the Windows API provides
some attributes that can be set on a window to ensure that it stays on
top.  So maybe this could be added as an option that is specific to
the Windows version of the GIMP.  But this should be low priority
(i.e., it will never be done unless someone submits a clean patch that
implements this feature).

Is there such an option for Windows systems?

I'm referring to confirguring the window manager.

No, this is not possible under Windows, except (maybe) if you install a
third-party window manager to replace the default one, but this is not
something that the average user could do.  It may be easier to install
Linux than to change the Windows WM and to configure it in the correct
way.

For Windows, the right way to ensure that the toolbox stays on top is
to change the code of the application (the GIMP) and to set the correct
attributes on the toolbox window.  This could be added as an option if
someone writes the code...

Huh? What is complicated about installing a different window manager
under windows? Download, click the setup icon, voila. Or am I missing
something?

Anyway, the real problem is that the Win32 GDK backend doesn't implement 
gdk_window_set_type_hint(). Or at least, it doesn't do anything
useful. So despite all the hints we set, they never end up at the
window manager level on Win32.

Hello again sven (or however you wish to be addressed).

Maybe I can help explain the issue from the perspective of a non-
Linux user.  First off, it must be stated that I do not know exactly 
what a window manager is -- I've never used one firsthand, and if I 
did, I didn't know I was using one. :)  I did a little bit of 
investigation into it, but the concept is still somewhat fuzzy.
Here's one of the places I invetigated:
http://www.plig.org/xwinman/

The concept of a "window manager" is foreign to the majority (like 
90-99% ) of Windows users who have never used another OS.  
Personally, I find no need to change the way the windows work in 
WinXP.  In fact, I actually find it detremental to begin making 
major changes to the way the system works; in many cases, it just 
results in more problems or it ends up being a waste of time.  It's 
not like Linux, where you MUST chose which desktop and window 
manager.

In the mindset of a Windows user, to ask them to change the way 
their system works so that an application will work correctly is a 
totally foreign philosophy.  To say to use a different window 
manager, is telling a Windows users to 1) use something they never 
have heard of or used before 2) to deviate from the default window 
manager that 99% of people use -- which may have problems in it 3) 
to adapt their system to an application, instead of the application 
working with the default.

Again, let it be mentioned that as far as I know, I've never used 
anything but a default window manager in Windows (or in another OS), 
so my understanding of the concept is not perfectly clear.  If 
anything, I wanted to mentioned that this bug report is a point of 
concern for Windows users.

Sure, but it is wrong to report it against GIMP. We will not special
case Windows since we are using GTK+/GDK which is supposed to hide the
differences. If the Windows port of GTK+/GDK doesn't support the flags
we set, than that is a GTK+/GDK bug and should be reported there. I'd
reassign this report to GTK+ but I suspect that this issue has already
been reported there. Perhaps you could check if that is the case.

Kevin is right when he says that the application should be adapted to
the system.  It should not be necessary for the users to adapt their
system to the application.

Regarding the "special case", there are two different issues here:
1) GTK+ should provide a function that allows a window to always "stay
   on top" for the Win32 platform
2) The GIMP should use this function to tell the window manager to put
   the toolbox window on top of all other windows.

The first issue is a GTK+ bug.  This should probably be done by using
gtk_window_set_type_hint() for a dock type (_NET_WM_WINDOW_TYPE_DOCK)
or something similar.  Unfortunately, this is not implemented yet, not
even for X11.  See also bug #87753 and bug #66719.

The second issue is a GIMP bug.  If the toolbox window should be
treated in a different way by the window manager (especially for
Windows), then the GIMP should call the appropriate function to tell
the WM to put this window on top of all others.

So although a part of this problem needs some things to be added to
GTK+, there is another part that is GIMP-specific (and would probably
have to be limited to Win32, because I don't think that X11 users
would like to have the toolbox always on top).

The GTK+ bug you mention is fixed and GIMP has been changed to set the
appropriate hints. There is an open issue with the toolbox since we
haven't decided what window hint to use here. It seems inappropriate
to handle it as an utility window like the other docks.

So is it correct to assume nothing can be done at the moment?

Is it possible to make them always on top for Windows builds (with 
an option to turn that feature off in the preferences) until the 
above mentioned fixes can be implemented.  Or is it best to wait?

We will certainly not add any code that is specific to the Windows
graphics system. We don't use any X11-specific code neither. So unless
GDK supports this, there's nothing the GIMP developers can do.

Raphaël, so what bug is this solution dependent on?

Changes at the request of Dave Neary on the developer mailing list.  
I am changing many of the bugzilla reports that have not specified a target
milestone to Future milestone.  Hope that is acceptable.  

You can now choose to have the utility type window hint being set on
the toolbox. Most window managers keep the window on top then.

*** Bug 129034 has been marked as a duplicate of this bug. ***