On removing the "TMP_Sub Mesh (Script)" component editor throw NullReferenceException, refer to the attached video.

Steps to repro:
1. Create a new project
2. Windows > Package Manager > TextMeshPro(3.00-preview.14) > Update.
3. Hierarchy > Right-click > Create Empty
4. Hierarchy > GameObject > Inspector > Add Component >TMP_Sub Mesh (Script) > Add
4. Hierarchy > GameObject > Inspector > TMP_Sub Mesh (Script) > Remove

Actual Result:
NullReferenceException is thrown on removing "TMP_Sub Mesh (Script)" component

Expected Result:
"TMP_Sub Mesh (Script)" component removed gracefully.

Reproducible in:
2020.2.0a18, 2020.2.0b16, 2020.1.0a11 with Package Version 3.0.0, 3.0.0-preview.14, 3.0.0-preview.1

Working fine in:
2020.1.0a11 with Package Version 2.1.0

Environment:
Windows 10 & macOS 10.14