The behavior you are experiencing with the "Collapse To Definitions" feature in Visual Studio 2026, where it only collapses the code within each #Region and leaves the regions themselves expanded, is not documented as a known bug or feature change in the provided context. Therefore, it is unclear whether this is intended behavior or an unintended issue introduced in the latest update.
To determine if this is a bug or a feature, you might consider checking the official release notes for Visual Studio 2026 or reporting the behavior to the Visual Studio community or support channels for further clarification.
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