Options Property dropdown under the Surface Effector 2D doesn't fully expand until the mouse cursor is moved in the Properties Window, refer to the attached video.

Steps to Reproduce:
1. Create a New Project
2. Hierarchy >right-click > Create Empty
3. Inspector > Surface Effector 2D > Add
4. Inspector > Surface Effector 2D > Burger Button > Open Properties window
5. Click on Options Property dropdown icon

Actual Result:
Options Property dropdown of "Surface Effector 2D" doesn't fully expand until the mouse cursor is moved

Expected Result:
Options Property dropdown of "Surface Effector 2D" expand irrespective of the mouse cursor

Note: Properties window is introduced in Unity 2020.1.0a19

Occurring in:
2020.2.0a9, 2020.1.0b8, 2020.1.0a19

Environment:
Windows 10 and Mac 10.14