Description:
I created several Page Styles in Calc. After saving and reopening the document, every Page Style I created, which was not assigned to a Sheet is gone.

Steps to Reproduce:
1. Create a new Calc document. Create new page Styles. Do not assign any Page Style to a Sheet.
2. Save and reopen the document.
3. Every recently created Page Style is gone.

Actual Results:
Every recently created Page Style is gone.

Expected Results:
Every Page Style I created and saved in the document should exist in the list of Page Styles in the Sidebar, even if it wasn't used in a Sheet. This was standard behavior befor 7.3.x (estimated)


Reproducible: Always


User Profile Reset: Yes

Additional Info:
Version: 7.3.7.2 (x64) / LibreOffice Community
Build ID: e114eadc50a9ff8d8c8a0567d6da8f454beeb84f
CPU threads: 4; OS: Windows 6.1 Service Pack 1 Build 7601; UI render: Skia/Raster; VCL: win
Locale: de-DE (de_DE); UI: de-DE
Calc: threaded