Not clear why, but with no Color Theme installed, using the 'System'|'Light'|'Dark' radio buttons to select color theme is not restoring the os/DE provided colors when returning to the 'System' radio buttons (rb).

Now no restart, and the 'Items' listbox in 'Customizations' goes inactive.

Choosing either 'Light' or 'Dark' Appearance rb, then setting rb to 'System' and Themes still on "Automatic" setting:

The 'Document background' is now "Black" not "Automatic" but also apparently the 'Font color' also "Black" rather than "Automatic".

Seems like we have a state where we don't restore colors back to os/DE provided colors for the "Automatic" theme and 'System' DE. Colors are set, but should roll back to "Automatic".

Noticed also, that any change to the Theme would require a restart, but no similar restart without a color theme and just "Automatic". 

Issue may be a simple as forcing the restart, without a color theme set, when just the change is made between the 'System'|'Light'|'Dark' radio buttons?

And, even with a color theme (Lime Theme) installed, changing the theme back to the Automatic lb entry--the Appearance options and Customization items don't restore the color values from os/DE. The Items lb remains inactive but the showing "Document bacground" shows Dark with a 'Black' color swatch. Can't see the 'Font color' item--but either automatic or black we get black or black on the document.


=-testing-=
Version: 25.2.0.1.0+ (X86_64) / LibreOffice Community
Build ID: 468d47bdf44a772e989a0adbeb5bb097e3cb4f31
CPU threads: 8; OS: Windows 10 X86_64 (10.0 build 19045); UI render: Skia/Vulkan; VCL: win
Locale: en-US (en_US); UI: en-US
Calc: CL threaded