-Graph Inspector window sticks to the mouse cursor on changing any dropdown value in Node settings.
-Workaround: Click anywhere to detach the Graph Inspector.

Steps to repro:
1. Create a new HDRP project.
2. Project Window > Click on "+" > Shader.
3. HDRP > StackLit Shader Graph > Open.
4. Blackboard Window > Add Float > Select.
5. Graph Inspector > Precision > Single/Half.

Actual Result:
Graph Inspector window sticks to the mouse cursor.

Expected Result:
Graph Inspector window should not stick to the mouse cursor.

Reproducible in:
2021.1.0a9, 2021.1.0a8

Working Fine in:
2020.2.0f1, 2021.1.0a7

Note: Unable to test on Mac due to this issue https://fogbugz.unity3d.com/f/cases/1294756/

Environment:
Occurring only on Windows.