Fix Image Resizer context menu appearing for unsupported file types

[Copilot]

Summary of the Pull Request

Image Resizer context menu appeared for PSD and other unsupported formats, failing with error on resize attempt. Fixed by adding extension whitelist validation before showing menu.

PR Checklist

• Communication: I've discussed this with core contributors already. If the work hasn't been agreed, this work might be rejected
• Tests: Added/updated and all pass
• Localization: All end-user-facing strings can be localized
• Dev docs: Added/updated
• New binaries: Added on the required places
  • JSON for signing for new binaries
  • WXS for installer for new binaries and localization folder
  • YML for CI pipeline for new test projects
  • YML for signed pipeline
• Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

Root cause: Context menu handlers relied on AssocGetPerceivedType() which returns PERCEIVED_TYPE_IMAGE for any Windows-registered image type (e.g., PSD via Photoshop). Image Resizer only processes WIC-compatible formats.

Changes:

• Added SupportedImageExtensions whitelist and validation function to ImageResizerConstants.h
• Updated both MSI (ContextMenuHandler.cpp) and MSIX (dllmain.cpp) handlers to validate extensions in QueryContextMenu() and GetState()
• Context menu now hidden for unsupported types regardless of Windows perceived type

Implementation:

// ImageResizerConstants.h
inline const std::vector<std::wstring> SupportedImageExtensions = {
    L".bmp", L".dib", L".gif", L".jfif", L".jpe", L".jpeg", L".jpg", 
    L".jxr", L".png", L".rle", L".tif", L".tiff", L".wdp"
};

inline bool IsSupportedImageExtension(LPCWSTR extension) { /* ... */ }

Single source of truth eliminates duplication between MSI/MSIX implementations.

Validation Steps Performed

Manual testing required:

• Verify PSD files no longer show Image Resizer context menu
• Verify supported formats (JPG, PNG, BMP, etc.) continue to show menu and resize correctly
• Test both regular right-click and drag-drop contexts

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Resize in Right Click Drag context menu for PSD files</issue_title>
<issue_description>### Microsoft PowerToys version

0.71.0

Installation method

PowerToys auto-update

Running as admin

Yes

Area(s) with issue?

Image Resizer

Steps to reproduce

Right-click drag any PSD file and you get "Resize Pictures Here" context menu, and when proceeding to resize it shows error "Can't resize the following pictures"

✔️ Expected Behavior

It shouldn't show the resize context menu as for all other non image files

❌ Actual Behavior

It shows resize here context menu

Other Software

No response</issue_description>

<agent_instructions>Implement a proper fix for this issue. Do NOT create placeholder stub files. Create actual working code that addresses the issue described. Follow PowerToys coding guidelines and conventions.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

@cinnamon-msft Are you still experiencing this issue? /needinfo

• Fixes Resize in Right Click Drag context menu for PSD files #27507

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