Description:
When selecting the "Style" separator line in the insert (and edit) menu of the columns section, the color of the lines in the drop-down list is set to the value set in the "Color" item. This leads to the fact that with a dark system theme, the color of the line is initially almost invisible to the user, and can also be set to a value corresponding to the background, due to which the line will not be visible at all.

It might be worth changing the current behavior in the "Style" drop-down list: keep the original color for lines, moving the preview somewhere else, or update the background color on which it is drawn to a sufficiently contrasting one along with the line color?

Steps to Reproduce:
1. Open Writer
2. Go to the menu "Insert" - "Section..." - "Columns"
3. For the "Columns" counter, set the value to 2 or more
4. Open the "Style" drop-down list and choose any line
5. In the "Color" field, select a line color value that matches the background color

Actual Results:
With the dark theme, the black color of the lines is initially difficult to see on a dark gray background.

The line color value can be set to a value that will completely blend in with the background color and make it difficult to select the desired line type.

Expected Results:
The line type in the "Style" list can always be distinguished, regardless of the selected color and OS or LO theme


Reproducible: Always


User Profile Reset: No

Additional Info:
Repro with:

Version: 25.8.0.0.alpha0+ (X86_64) / LibreOffice Community
Build ID: 38a4d3f0b095f70deaf1c25617b5f8b378f31626
CPU threads: 12; OS: Linux 6.6; UI render: default; VCL: kf5 (cairo+xcb)
Locale: ru-RU (ru_RU.UTF-8); UI: en-US
Calc: CL threaded

Exists at least in:

Version: 6.0.0.1
Build ID: d2bec56d7865f05a1003dc88449f2b0fdd85309a
CPU threads: 12; OS: Linux 6.6; UI render: default; VCL: gtk2;
Locale: ru-RU (ru_RU.UTF-8); Calc:CL