Enforce Global Namespace in XAML

In XAML, a custom namespace can be imported with an xmlns directive:

xmlns:custom="clr-namespace:GreatStuff"

In C#, that namespace can be imported with

using GreatStuff;

Moreover, evaluation of that namespace based on the global (root) namespace can be enforced as follows:

using global::GreatStuff;

How can I enforce evaluation based on the global namespace in XAML?

Background:

I am facing the (admittedly slightly obscure) situation that there is such a namespace global::GreatStuff, which contains a WPF control class named ... GreatStuff (i.e. fully qualified, that's global::GreatStuff.GreatStuff in C#). In the same namespace, I want to use that control in a WPF window.

Interestingly, in this constellation, I cannot use the Name/x:Name attribute on any controls of type global::GreatStuff.GreatStuff in my XAML file for the window:

The type name 'GreatStuff' does not exist in type 'GreatStuff.GreatStuff'. (CS0426)

Note that the very same file compiles fine if I do not specify a Name/x:Name attribute!

Now, why should the compiler assume that by setting a Name/x:Name attribute, I am trying to access something called GreatStuff.GreatStuff.GreatStuff?

The answer can be found by examining the .g.cs file generated from the window XAML file. In that file, the XAML snippet

<custom:GreatStuff x:Name="stuff"/>

gets compiled to the following C# snippet:

internal GreatStuff.GreatStuff stuff;

That is, the fully-qualified name is used, but without the explicit global namespace marker.

Of course, as a field in a class in namespace global::GreatStuff, all of this is wrapped in

namespace GreatStuff {

And so, the poor C# compiler cannot help but assume that stuff is supposed to be of a type global::GreatStuff.GreatStuff.GreatStuff. This could be avoided if in

xmlns:custom="clr-namespace:GreatStuff"

I could enforce that any mentions of that namespace prefix could be converted while enforcing the global namespace.

For reasons external to this question, changing the namespace and/or class names is not an option here.

This issue only occurs when all of the following are true:

You have a class with an identical name as the namespace containing it.
Within that same namespace, you have a xaml file with an instance of an object that is also declared within that namespace.
That specific object instance is given a Name or x:Name attribute.

If you cannot modify anything to make any one of those conditions false, then you are working with some very serious restrictions.

As far as I know, this is a limitation of the xaml compiler, and you will need to contact Microsoft about resolving it. The only other thing I can think of would be to try to work around it with a custom build process that builds xaml, allows you to edit the generated files, then builds the code. That would require some research to figure out how to set up.