Tabs Block - Separator block is not visible

[malalacharm]

Describe the bug
When a Separator block is added inside a Tabs block, it does not appear in the editor and frontend.

• happens in editor
• happens on frontend

To Reproduce
Steps to reproduce the behavior:

1. Add a Tabs Block
2. Add a Separator block in the first Inner Column
3. See error in the editor
4. See error in the frontend

Expected behavior
The Separator block should render as a visible horizontal line within the tab panel.

Screenshots