Positions size index values are getting clipped in the Line Renderer component.

Steps to repro:
1. Create a new project.
2. GameObject> Create Empty > Add Component > Line Renderer.
3. Expand Positions property > Enter size index value.

Actual Result:
Positions size index values are getting clipped.

Expected Result:
Positions size index values are not getting clipped

Reproducible in:
2020.1.0a2.

Working Fine in:
2020.1.0a1, 2019.3.0b1.

Environment:
Windows & Mac 10.14.