fix(use-sticky): inconsistent fallback target

[Dashice]

Previously, element used to determine stickiness was the document.body. This worked on sites whose body was styled in an opinionated manner. This has been replaced with a representation of Viewport instead, meaning the dimensions of your browser window over arbitrary body dimensions, which can overflow / underflow the Viewport.

[changeset-bot]

🦋 Changeset detected

Latest commit: 58400ad

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@noaignite/react-utils	Patch

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Project	Deployment	Actions	Updated (UTC)
docs	Ready	Preview, Comment	Feb 26, 2026 0:59am

[codecov]

Codecov Report

❌ Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
packages/react-utils/src/useSticky.ts	0.00%	3 Missing ⚠️

❌ Your patch check has failed because the patch coverage (0.00%) is below the target coverage (90.00%). You can increase the patch coverage or adjust the target coverage.

@@           Coverage Diff           @@
##             main     #553   +/-   ##
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  Coverage   67.86%   67.86%           
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  Files          63       63           
  Lines         974      974           
  Branches      246      246           
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  Hits          661      661           
  Misses        254      254           
  Partials       59       59           

Files with missing lines	Coverage Δ
packages/react-utils/src/useSticky.ts	0.00% <0.00%> (ø)

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[maeertin]

LGTM

[Copilot]

Pull Request Overview

This PR fixes an inconsistency in the useSticky hook by replacing the fallback from document.body to viewport dimensions when no container is provided. This ensures consistent behavior regardless of how the document body is styled.

• Replaces document.body fallback with viewport-based dimensions using window.innerHeight and window.innerWidth
• Removes the parent element validation check since the parent can now be null
• Updates the logic to handle cases where no container is provided by using a synthetic viewport rectangle

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
packages/react-utils/src/useSticky.ts	Updates sticky positioning logic to use viewport dimensions as fallback instead of document.body
.changeset/rare-dancers-beam.md	Documents the change for release notes

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Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

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