NullReferenceException is thrown on clicking on the record button of the Timeline clip. Unable to record the Timeline clip.

Steps to repro:
Create a new Project.
Gameobject > 3D Object > Cube.
Windows > Sequencing > Timeline > Dock the Window.
Select the Cube game object.
Click on the Record button in Timeline Window.

Actual Result:
Unable to record the Timeline clip due to NullReferenceException.

Expected Result:
Timeline clip should be recorded.

Reproducible in:
2020.1.0a7.

Working Fine in:
2020.1.0a6, 2019.3.0b5.

Tested on Package Version: 1.2.2.

Workaround:
Remove the Timeline Package and install again.

NOTE: Refer attached Stacktrace.

Environment:
Only on Windows.