Created attachment 182780 [details]
Presentation for reproducing the bug

Reproduction steps:

1. Open LO Impress with a new presentation
2. On the menus, Insert | Table.
3. Choose 3 columns and 2 rows
4. Enter some text in the cells of the first row, e.g. "one", "two", "three"
5. Place the cursor in the middle cell of the top column
6. Right click to get the context menu
7. On the context menu, choose "Insert Column After"
8. Move your cursor to the newly-created column.
9. Type "huh?"

Expected behavior:

After step (4.), the text is set at Liberation Sans 18pt, and is not bulleted;
After step (7.), the text in the newly-created column is set in Liberation Serif 24 pt, and is bulleted.

Notes:

* Same behavior if you "Insert Column Before"

Build info:
Version: 7.4.1.2 / LibreOffice Community
Build ID: 3c58a8f3a960df8bc8fd77b461821e42c061c5f0
CPU threads: 4; OS: Linux 5.4; UI render: default; VCL: qt5 (qfont+xcb)
Locale: en-GB (en_GB.UTF-8); UI: en-US

and also seeing this with:
Version: 7.3.6.2 / LibreOffice Community
Build ID: 30(Build:2)
CPU threads: 4; OS: Linux 5.4; UI render: default; VCL: gtk3
Locale: en-GB (en_GB.UTF-8); UI: en-US
Ubuntu package version: 1:7.3.6-0ubuntu0.22.04.1~bpo20.04.1