Package dropdown does not collapse for packages having multiple versions when other versions of the same package are selected from the dropdown list. Refer the attached video

Steps to reproduce:
1) Create a new project
2) Window > Package Manager
3) Click on dropdown of 2d Animation > Select 4.1.0 version
4) Click on dropdown of 2D Animation

Actual result: Dropdown list of 2D Animation does not collapse

Expected result: Dropdown list of 2D Animation should collapse

Workaround: Select 2D Animation package and then click on the dropdown. The version list will collapse and work as expected

Occurring on: 2020.1.0a20, 2020.1.0a19

Working fine on: 2020.1.0a18, 2019.3.0f6

Environment: Both Windows and Mac