microsoft / microsoft/vscode-custom-data

`scroll-marker-group` CSS property flagged as 'Unknown property'

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#120 9 comments 0 reactions 1 assignee View on GitHub

@aeschli is already working on this.

Since Jun 19, 2025.

feature-request
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JavaScript
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Description

Does this issue occur when all extensions are disabled?: Yes

  • VS Code Version: 1.101.0 (Universal)
  • OS Version: macOS Sequoia Version 15.5

Steps to Reproduce:

  1. Disable all VSCode extensions. This bug is not related to extensions.
  2. Create a .css file.
  3. Try to apply the scroll-marker-group property to an element. For example:
    ul {scroll-marker-group: after;}
  4. Note the blue squiggly highlighting and VSCode error
    Unknown property: 'scroll-marker-group' css(unknownProperties)
  5. scroll-marker-group is indeed a valid property. The scroll-marker-group property is used to control whether a scroll container has a ::scroll-marker-group pseudo-element generated. This bug was identified while following the MDN tutorial for creating a CSS carousel.

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