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## Fixes#4225
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## PR Type
What kind of change does this PR introduce?
<!-- Please uncomment one or more options below that apply to this PR. -->
- Bugfix
<!-- - Feature -->
<!-- - Code style update (formatting) -->
<!-- - Refactoring (no functional changes, no api changes) -->
<!-- - Build or CI related changes -->
<!-- - Documentation content changes -->
<!-- - Sample app changes -->
<!-- - Other... Please describe: -->
## What is the current behavior?
Compilation fails If the Microsoft MVVM Toolkit source generator attribute `[ObservableProperty]` is in a `#region` block.
<!-- Please describe the current behavior that you are modifying, or link to a relevant issue. -->
## What is the new behavior?
The generated code is now correct when regions are used.
<!-- Describe how was this issue resolved or changed? -->
## PR Checklist
Please check if your PR fulfills the following requirements: <!-- and remove the ones that are not applicable to the current PR -->
- [X] Tested code with current [supported SDKs](../#supported)
- [X] New component
- [X] Pull Request has been submitted to the documentation repository [instructions](../blob/main/Contributing.md#docs). Link: <!-- docs PR link -->
- [X] Added description of major feature to project description for NuGet package (4000 total character limit, so don't push entire description over that)
- [X] If control, added to Visual Studio Design project
- [X] Sample in sample app has been added / updated (for bug fixes / features)
- [X] Icon has been created (if new sample) following the [Thumbnail Style Guide and templates](https://github.com/CommunityToolkit/WindowsCommunityToolkit-design-assets)
- [X] New major technical changes in the toolkit have or will be added to the [Wiki](https://github.com/CommunityToolkit/WindowsCommunityToolkit/wiki) e.g. build changes, source generators, testing infrastructure, sample creation changes, etc...
- [X] Tests for the changes have been added (for bug fixes / features) (if applicable)
- [X] Header has been added to all new source files (run _build/UpdateHeaders.bat_)
- [X] Contains **NO** breaking changes
## Related to #3650
Splitting out the upgrade to WinUI 2.6 in the Unit Tests project to help try and isolate what might be going on.
Noticed some our other NuGet dependencies have updates as well, so if this works as-is, will try and update those as well.
Then we can check this in, and rebase #3650 to try and determine what else might be going on or pull in others to help investigate.
FYI @huynhsontung @azchohfi
## PR Type
What kind of change does this PR introduce?
<!-- Please uncomment one or more options below that apply to this PR. -->
<!-- - Bugfix -->
<!-- - Feature -->
<!-- - Code style update (formatting) -->
- Refactoring (no functional changes, no api changes)
<!-- - Build or CI related changes -->
<!-- - Documentation content changes -->
<!-- - Sample app changes -->
<!-- - Other... Please describe: -->
## What is the current behavior?
WinUI 2.6 not included when we run unit tests
## What is the new behavior?
WinUI 2.6 is now included when we run unit tests.
## PR Checklist
Please check if your PR fulfills the following requirements:
- [ ] Tested code with current [supported SDKs](../readme.md#supported)
- [ ] Pull Request has been submitted to the documentation repository [instructions](..\contributing.md#docs). Link: <!-- docs PR link -->
- [ ] Sample in sample app has been added / updated (for bug fixes / features)
- [ ] Icon has been created (if new sample) following the [Thumbnail Style Guide and templates](https://github.com/CommunityToolkit/WindowsCommunityToolkit-design-assets)
- [ ] New major technical changes in the toolkit have or will be added to the [Wiki](https://github.com/CommunityToolkit/WindowsCommunityToolkit/wiki) e.g. build changes, source generators, testing infrastructure, sample creation changes, etc...
- [ ] Tests for the changes have been added (for bug fixes / features) (if applicable)
- [ ] Header has been added to all new source files (run *build/UpdateHeaders.bat*)
- [ ] Contains **NO** breaking changes
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## Other information
Remove redundant MSBuild logic
Consolidate common MSBuild logic
Reorder code-blocks for better readability
Fix-up comments and new-lines across project files
Improve support for Visual Studio 2022:
Since VS IDE 2022 (17.0) is 64-bit only, replace all 32-bit specific MSBuild properties with generic ones.
Sergio Pedri