Issue with compactType={null} and preventCollision={false} causing unexpected Y-axis movement in version 1.5.0

[hkpark130]

Describe the bug

In React-Grid-Layout 0.18.3 , when compactType is set to null and preventCollision={false}, elements are arranged as expected.
However, in version 1.5.0 , grid items unexpectedly shift along the Y-axis , which is not the expected behavior.
➡️ I want to use version 1.5.0 but maintain the positioning behavior of 0.18.3.

Your Example Website or App

https://codesandbox.io/p/sandbox/1-5-0-grid-96w46p

Steps to Reproduce the Bug or Issue

1. Set compactType=null and preventCollision={false}.
2. In 0.18.3 , layout behaves as expected.
3. In 1.5.0 , items unexpectedly move along the Y-axis instead of keeping their original positions.

Expected behavior

The grid layout in 1.5.0 should behave the same way as in 0.18.3 .
Items should not be dramatically moved along the Y-axis when preventCollision={false}.

react-grid-layout library version

1.5.0

Operating System Version

Windows

Browser

Chrome

Additional context

Actual Behavior

• In 1.5.0 , items shift dramatically along the Y-axis , unlike version 0.18.3.

Reproducible Example (CodeSandbox)

✔️ Version 0.18.3 (Works as expected)
🔗 CodeSandbox - 0.18.3

❌ Version 1.5.0 (Unexpected Y-axis movement)
🔗 CodeSandbox - 1.5.0

Environment

• "react": "^18.0.0",
• "react-dom": "^18.0.0",
• "vite": "^6.2.1"

Additional Context

• When compactType=null and preventCollision=false, items remain in place and overlap in 0.18.3 but are forcibly moved down (Y-axis) in 1.5.0 .
• Was there a change in the compaction logic after 0.18.3?
• Is there any workaround or setting available to retain the old behavior while still using version 1.5.0?

🙇 Please let me know if this can be resolved. Thank you! 🙏

Screenshots or Videos

• (0.18.3 working)
  

• (1.5.0 issue)