Description:
THE PROBLEM : 
- I create a [3 col x 5 rows] table. Change police, put bold and center it. 
- fill all cells. 
- I duplicate this table (with an empty line between)
- I choose to add a row. 
BAM ! It happens. 
All text format is gone. THe text is here, but back to default font, and everything.

HOW TO REPRODUCE : 
i made a exemple doc that trigger at every try the bug. 

BONUS POINT : 
try to abort changes. (spoiler : it remove the row, but doesn't get back text format. It's lost!)


Steps to Reproduce:
1. I create a [3 col x 5 rows] table. Change police, put bold and center it. 
2. fill all cells. 
3. I duplicate this table (with an empty line between)
4. I choose to add a row. 


Actual Results:
- Formating is destroyed, back to defalut texte format. 
- format erasing can NOT be reversed with CTRL+Z

Expected Results:
- no text format in the table is erased
- no unexpected behaviour that cannot be reversed with CTRL+Z


Reproducible: Always


User Profile Reset: Yes


OpenGL enabled: Yes

Additional Info:
I made a attachement with an exemple to reproduce. 

I tryed safe mode. Nope, it doesn't solve it.

OPen GL report : 

Rendereur: GeForce RTX 2080 SUPER/PCIe/SSE2
Fournisseur: NVIDIA Corporation
Version:4.6.0 NVIDIA 457.51 
Version GLSL: 4.60 NVIDIA                   


Max. taille texture 32768 x 32768
Max. vertex tex. image units: 32
Max. texture image unit?s 32
Max Geometry Texture Units: 32
Max. anisotropie 16
Taille Max. Vue 32768 x 32768
Distances maximales des clips: 8
Max. ?chantillons 16


Extensions: 428