Deletion Marker of deleted line at wrong position

> @hediet I assume this is for testing with your hybrid markdown editor, is that correct? That one did not open for me even though I had `workbench.editor.markdownDefaultEditorInAgentsWindow` enabled. I had to call `View: Reopen Editor with...` -> `Markdown Editor (Experimental)`
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> I wasn't sure so I tested with all three editors (1. Text Editor, 2. Markdown Preview, 3. Markdown Editor (Experimental)):
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> ### 1. Text Editor
> works fine
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> ### 2. Markdown Preview
> I don't see any markers
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> ### 3. Markdown Editor (Experimental)
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> I see markers, but the position of the deletion marker changes depending on which line my cursor is in
>
> https://github.com/user-attachments/assets/dd2dced0-659c-4ea4-a328-9f0403328221
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_Originally posted by @Giuspepe in [#326541](https://github.com/microsoft/vscode/issues/326541#issuecomment-5023990300)_