Thanks for helping to improve the WPF Designer.
In order for your changes to be accepted, please add the following statement to your pull request:
I certify that I own, and have sufficient rights to contribute, all source code and related material intended to be compiled or integrated with the source code for the WPF Designer open source product (the "Contribution"). My Contribution is licensed under the MIT License.
Unless we have this statement in your pull request, we cannot accept it.
Please be aware that we will not accept pull requests which introduce new dependencies (to UI DLLs) to the WPF Designer. Reason: it is not possible to edit XAML screens which use these DLLs, when they for example have different versions.