Bug (Case 1298763) Drag&drop asset package on Unity freezes Unity and Windows Explorer

Drag&drop a bigger asset package from Windows Explorer to Unity, causes Unity and Windows Explorer to freeze for a significant amount of time.

Reproduce

• Buy https://assetstore.unity.com/packages/audio/sound-fx/pro-sound-collection-50235
• Drag&Drop package from "C:\Users\%UserName%\AppData\Roaming\Unity\Asset Store-5.x\Gamemaster Audio\AudioSound FX"

Actual
Unity and Windows Explorer freeze.

Expected
No freeze or at least it should not freeze Windows Explorer.

 

QA was able to reproduce:
https://issuetracker.unity3d.com/is...the-asset-import-process-by-drag-and-dropping