Creating rows fails

Issue found

• Adding rows seem not to work when clicking on the plus icon. It actually creates rows, but those are not visible. They may become visible when the screen is resized.
• After resizing, numbers on rows do not exist.
• Snapshot: 186
• MacOS, M1

How to reproduce

1. Take the latest snapshot
2. Open Model editor from view menu
3. Create a model
4. Create a few columns
5. Create a row, possibly delete one, and try to create a new one
6. You may see this: AddRowFails.mp4
7. After adjusting height of the panel, rows that may have been created are visible. Row numbers are missing, until you delete a row. 
   

How it is expected to work

• The user should see the rows created, and the view should have scrollbars to give the user a hint that some rows are added.
• Rows should have numbers.
• Vertical scrolling should scroll so, that header of the table stays visible. Only rows are scrolling