You didn’t mention how you format your lists. I’ll suppose you do that with the toolbar buttons. This is a quick’n’dirty way which should be reserved for tests or one-shot documents.
Pressing the Toggle Numbered List button or
F12 makes the current paragraph a numbered list item. The “number” is controlled by character style Numbering Symbols. Modify this style to get the effects you want.
Pressing the Toggle Bulleted List button or
F12 makes the current paragraph a bulleted list item. The “bullet” is also controlled by Numbering Symbols.
The problem is that using the toolbar buttons is direct formatting, meaning you cannot change anything afterwards with character style modifications. The bullet/number takes the formatting in effect at the time you create the list.
The “correct” (that’s a personal opinion) way to address list formatting is through styles. Unfortunately, mastering this LO Writer aspect is quite difficult because it involves three styles: the paragraph style for the “raw” item, a numbering style (called list in LO parlance) for the bullet/number/level general layout and a paragraph style for the visual aspects of the bullet/number (such as colour, weight, font, size, …).
The list style is defined in
Outline & Numbering tab of the paragraph style.
Note that, by default, built-in styles List n and Numbering n paragraph styles have no linked list styles, so that, not modified by user, they behave as ordinary paragraph styles and don’t result in lists.
The character style is defined in
Customize tab of the list style. In this same tab, you can choose the bullet character (per level) or the kind of numbering.
Take the time to experiment to see the interactions between the styles.
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