[WIP] Fix copy keyboard shortcut issue in Windows app

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

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This section details on the original issue you should resolve

<issue_title>Copy kb shortcut fails on Windows app</issue_title>
<issue_description>Wonderful tool and UX! Found what appears to be a copy-paste bug in the windows build so wanted to report it
Steps to reproduce:

1. OS: Windows 11v25H2 Build 26200.8246 with current updates
2. Download and run the windows desktop-v2026.2.0 release's exe
3. Select text anywhere in the editor or preview pane (in any viewing mode)
4. press Ctrl+C to attempt to copy
5. Paste into a text editor or similar
6. Note that the entire document has been pasted, not just your selection</issue_description>

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Project	Deployment	Actions	Updated (UTC)
markdown-viwer	Ready	Preview, Comment	Apr 26, 2026 10:38am